A127436 Primes associated with A127435.

2, 5, 17, 37, 101, 257, 1297, 1601, 4357, 15877, 16901, 22501, 24337, 32401, 44101, 57601, 62501, 65537, 72901, 78401, 93637, 156817, 160001, 176401, 184901, 217157, 240101, 309137, 324901, 331777, 417317, 476101, 490001, 562501, 577601, 682277

Offset

1,1

Comments

A sequence with P=a(k) distinct numbers contains a subsequence of p=A127435(k) monotonically increasing or decreasing terms, according to a corollary of the Erdos-Szekeres theorem.

Links

Table of n, a(n) for n=1..36.

Formula

a(n) = (A127435(n)-1)^2 + 1.

Mathematica

Select[(Prime@Range[300] - 1)^2 + 1, PrimeQ] (* Ray Chandler, Jan 23 2007 *)

Prog

(PARI) listp(nn) = {forprime(p=2, nn, if (isprime(q=(p-1)^2 + 1), print1(q, ", ")); ); } \\ Michel Marcus, Jun 08 2016

Crossrefs

Cf. A127435. Subsequence of A045349.

Sequence in context: A346809 A276460 A002496 * A064168 A118727 A183906

Adjacent sequences: A127433 A127434 A127435 * A127437 A127438 A127439

Keyword

nonn

Author

Lekraj Beedassy, Jan 14 2007

Extensions

Corrected and extended by Ray Chandler, Jan 23 2007

Status

approved