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A211389 revision #5

A211389

a(n)is the first occurance of n in sequence A209266

3, 5, 9, 14, 16, 26, 54, 67, 74, 103, 161, 293, 236, 432, 249, 788, 1078, 796, 1885, 2091, 1712, 2618, 4099, 7088, 8137, 8091, 16086, 12595, 27627, 22835, 44576, 31305

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..32.

EXAMPLE

A209266={1, 1, 2, 2, 2, 1, 3, 3, 1, 3, 3, 4, 3, 5, 4, 2, 5, 4, 4, 4, 4, 3, 3, 6, 6, 4,...} starting from A209266(3)=1.

Number 1 first appears as A209266(3), number 2 as A209266(5), number 3 as A209266(9)...

So, a = {3, 5, 9, ...} starting from a(1)=3.

MATHEMATICA

aim = 32; a = Table[0, {i, 1, aim}]; zeros = aim; i = 2; While[i++;

p = Prime[i]; ct = 0; Do[If[(PrimeQ[p - j]) && (PrimeQ[p + j]),