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A127436 Primes associated with A127435. 4
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 (list; graph; refs; listen; history; text; internal format)
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: A240322 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

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Last modified January 22 08:58 EST 2018. Contains 298042 sequences.