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## #26 2011-05-20 06:22:08

John E. Franklin
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### Re: Let's make triangular numbers.

351
a triangle with 26 rows, pair them up for 13 pairs of 27.
270 + 81 = 351, yup.

Imagine for a moment that even an earthworm may possess a love of self and a love of others.

## #27 2011-05-20 12:41:09

bobbym

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### Re: Let's make triangular numbers.

378

Is the sum of two other traingular numbers.

378 = Triangular(12) + Triangular(24)

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #28 2011-05-25 22:02:10

bob bundy
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### Re: Let's make triangular numbers.

I see what you’re up to here.

Everyone is holding off from posting because you all want to hit post #31.

So I’m going to have it this way.

The North Circular Road around  inner London = 406

Bob

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

## #29 2011-05-25 22:04:40

bob bundy
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### Re: Let's make triangular numbers.

Then

(root(4) x 10 + (4 + 5)) x 3 x 5 = 435

Bob

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

## #30 2011-05-25 22:06:44

bob bundy
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### Re: Let's make triangular numbers.

Triangular  45 with a triangular 6 between = 465

Bob

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

## #31 2011-05-25 22:08:01

bob bundy
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### Re: Let's make triangular numbers.

496  Arrrrhh!  That’s perfect!

Bob

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

## #32 2011-05-26 00:56:40

bobbym

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### Re: Let's make triangular numbers.

528

2^9 + 2^4 = 528

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #33 2011-05-26 06:29:05

anonimnystefy
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### Re: Let's make triangular numbers.

561

if HCF(561,b)=1 then b^560 is congruent to 1 modulo 561

Last edited by anonimnystefy (2011-08-15 20:39:57)

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #34 2011-05-26 07:10:04

bobbym

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### Re: Let's make triangular numbers.

595

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #35 2011-05-26 07:15:28

anonimnystefy
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### Re: Let's make triangular numbers.

630=2*3*3*5*7=97+101+103+107+109+113 which are consecutive primes

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #36 2011-05-26 07:50:48

bobbym

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### Re: Let's make triangular numbers.

666

The mark of the beast.

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #37 2011-05-26 20:19:21

anonimnystefy
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### Re: Let's make triangular numbers.

703-a Kaprekar number

Last edited by anonimnystefy (2011-05-26 20:22:06)

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #38 2011-08-15 07:28:39

anonimnystefy
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### Re: Let's make triangular numbers.

740-a non-totient number

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #39 2011-08-15 16:34:26

bobbym

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### Re: Let's make triangular numbers.

Hi;

741 a triangular number.

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #40 2011-08-15 20:34:40

anonimnystefy
Real Member

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### Re: Let's make triangular numbers.

oh yes you are right

catching up:
780-also a hexagonal number,Harshad number,sum of ten consecutive primes:

780=59 + 61 + 67 + 71 + 73 + 79 + 83 + 89 + 97 + 101

8+2+0|820

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #41 2012-07-05 02:58:55

John E. Franklin
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### Re: Let's make triangular numbers.

861 = 41 + 820

41 by 21 = 800 + 1 + 40 + 20

Imagine for a moment that even an earthworm may possess a love of self and a love of others.

## #42 2012-07-05 03:24:12

bobbym

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### Re: Let's make triangular numbers.

Hi;

903 not a prime.

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #43 2012-07-05 03:27:26

anonimnystefy
Real Member

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### Re: Let's make triangular numbers.

946-not a prime either.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #44 2012-07-05 03:29:22

bobbym

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### Re: Let's make triangular numbers.

990 almost a prime.

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #45 2012-07-05 03:33:24

anonimnystefy
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### Re: Let's make triangular numbers.

1035-first triangular number greater than 1000.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #46 2012-07-05 03:36:30

bobbym

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### Re: Let's make triangular numbers.

1081 also not a prime.

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #47 2012-07-05 03:40:46

anonimnystefy
Real Member

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### Re: Let's make triangular numbers.

1128-not not a not-prime

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #48 2012-07-05 03:42:33

bobbym

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### Re: Let's make triangular numbers.

1176 add 600 and it has meaning today!

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #49 2012-12-14 17:10:59

julianthemath
Super Member

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### Re: Let's make triangular numbers.

Buy 1 for \$1, for \$0.50, for \$3, for \$2.50, for \$1.25, for \$0.25, and for \$5.

## #50 2012-12-14 19:44:41

bobbym

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### Re: Let's make triangular numbers.

The next triangular number is 1275.

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.