Member Avatar for hamada_1990

nope that ain't it guess again

Duki commented: what is your problem? stop posting mindless junk! -2
Member Avatar for christina>you

1511

1523

Member Avatar for BearofNH

1531

The smallest prime that is also a sum of primes beginning and ending with the digit seven (1531 = 7 + 727 + 797). Well, excluding the degenerate case of 7 by itself...

Member Avatar for mayank_ati

1543

Member Avatar for BearofNH

1549

The smallest odd number that is not the sum of a prime and a power > 1 (!)

For examples:
1543 = 1511 + 2^5
1531 = 1523 + 2^3
1523 = 1459 + 8^2

... but no such equation for 1549.

Member Avatar for mayank_ati

1553
@above BearofNH
are you doing any master cource in prime numbrs????

Member Avatar for BearofNH

1559

As we all know, every number is interesting. I'm just pointing out some of the reasons why.

But yes, I did my master's in number theory very long ago. I studied under Gauss.

Member Avatar for mayank_ati

1567
that's gr8......

Member Avatar for BearofNH

1571

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1579

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1583

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1601

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1607

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1613

Member Avatar for valerium

1621

There are 98 million primes less than 2000000000, so we could be here for a while :-)

Member Avatar for BearofNH

1657

Third of 3 primes in a row, all ending in 7

Member Avatar for blrouley

OK, I am new to this, but is there a simple test for a number being prime? The number obviously cannot end in an even number or with a five or a zero. So we eliminate testing division by 2, 4, 5, 6, 8, and 10 immediately. Any number divisible by 9 is also divisible by 3, so it seems the first tests are to find if the next number is divisible by 3, 7, 11, 13, 17, etc., to include other prime numbers as we progress. Does this make sense?

It seems that 1667 is the next number that passes these tests.

Member Avatar for christina>you

It seems that 1667 is the next number that passes these tests.

Actually I thought the next one would be 1663.

Member Avatar for jasimp

1669 is the next after 1667

Member Avatar for valerium

A big jump to the next one which is .....

1693

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small jump of four to 1697

Member Avatar for scudzilla

An even smaller jump... 1699

Member Avatar for jasimp

1709

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