A105050 - OEIS

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A105050

a(0)=2, a(n) is the smallest prime of the form a(n-1)*k^2 + 1.

2, 3, 13, 53, 30529, 122117, 17584849, 70339397, 22789964629, 11030342880437, 9927308592393301, 91490075987496662017, 23421459452799145476353, 918214896387537699254943013, 528891780319221714770847175489, 8665362928750128574805560123211777, 311953065435004628693000164435623973

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,1

LINKS

Table of n, a(n) for n=0..16.

EXAMPLE

a(5) = 30529 = 53*24^2 + 1 is the smallest prime of the form 53*k^2 + 1.

PROG

(PARI) lista(nn) = my(k, p=2); print1(p); for(n=1, nn, k=1; while(!isprime(p*k^2+1), k++); print1(", ", p=p*k^2+1)); \\ Jinyuan Wang, Aug 02 2021

CROSSREFS

Cf. A061092, A093490.

Sequence in context: A203985 A164511 A184256 * A184179 A100102 A208202