A154505 Sophie Germain primes of A144571.

1601, 240101, 1464101, 2755601, 6100901, 72250001, 75342401, 139948901, 281568401, 284596901, 325441601, 351937601, 655360001, 683299601, 702250001, 1479940901, 1621672901, 1830984101, 2168764901, 2219352101, 2544193601

Offset

1,1

Links

Table of n, a(n) for n=1..21.

Mathematica

lst={}; Do[If[PrimeQ[p=81*n^2-90*n+26], If[PrimeQ[2*p+1], AppendTo[lst, p]]], {n, 8!}]; lst
Select[Table[81 n^2-90 n+26, {n, 6000}], AllTrue[{#, 2#+1}, PrimeQ]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jun 09 2021 *)

Crossrefs

Cf. A144571, A154503, A154504

Sequence in context: A078853 A078958 A031758 * A031538 A202774 A293370

Adjacent sequences: A154502 A154503 A154504 * A154506 A154507 A154508

Keyword

nonn

Author

Vladimir Joseph Stephan Orlovsky, Jan 11 2009

Status

approved