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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A091277 Numbers k such that the k-th prime is of the form m^2 + (m+1)^2.

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%I A091277 #14 Aug 02 2021 12:17:22
%S A091277 3,6,13,18,30,42,65,82,112,135,170,197,212,271,284,319,353,369,445,
%T A091277 505,612,682,933,1069,1193,1226,1286,1510,1609,1676,1711,1789,1900,
%U A091277 2161,2241,2285,2363,2450,2667,2712,2924,3247,3644,3894,4000,4100,4367,4647,4922
%N A091277 Numbers k such that the k-th prime is of the form m^2 + (m+1)^2.
%C A091277 Also, the k-th prime is of the form (m^2+1)/2.
%H A091277 Jinyuan Wang, <a href="/A091277/b091277.txt">Table of n, a(n) for n = 1..1000</a> (terms 1..500 from Harvey P. Dale)
%F A091277 a(n)=k such that A000040(k)=A027862(n).
%t A091277 Select[Range[5000],OddQ[Sqrt[2Prime[#]-1]]&] (* _Harvey P. Dale_, Jun 25 2018 *)
%Y A091277 A027862 indexed by A000040.
%Y A091277 Cf. A002731, A027861, A027862.
%K A091277 nonn,easy
%O A091277 1,1
%A A091277 _Ray Chandler_, Jan 03 2004
%E A091277 Offset changed to 1 by _Jinyuan Wang_, Aug 02 2021