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%I #26 Jun 27 2024 22:18:12
%S 2,3,5,7,13,20,24,26,28,30,31,32,36,41,43,49,52,62,64,67,69,73,77,81,
%T 83,86,87,89,103,105,109,116,121,129,135,142,144,148,152,156,158,159,
%U 163,168,171,173,182,190,192,196,206,208,212,215,217,219,223,225,231,234,236
%N Numbers k such that prime(k+1) == 1 (mod (prime(k+2) - prime(k))).
%H G. C. Greubel, <a href="/A178570/b178570.txt">Table of n, a(n) for n = 1..10000</a>
%e 2 is a term because prime(2+1) mod (prime(2+2) - prime(2)) = 5 mod 4 = 1.
%t fQ[n_] := Mod[Prime[n+1], Prime[n+2] - Prime[n]] == 1; Select[ Range@ 250, fQ]
%o (PARI) isok(n) = prime(n+1) % (prime(n+2) - prime(n)) == 1; \\ _Michel Marcus_, Jan 31 2019
%Y Cf. A067185.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Jan 01 2011