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%I #7 Nov 22 2022 22:20:13
%S 4,17,38,41,48,56,57,75,104,109,112,120,131,162,166,186,189,196,201,
%T 220,241,273,274,293,341,360,389,421,428,466,467,510,522,555,601,607,
%U 623,631,635,669,684,685,704,711,712,735,763,793,815,823,824,831,832
%N Indices of the primes in A181424.
%C This sequence, together with A358529 and A358531, partition the set of positive integers >= 3.
%F a(n) = A064113(n) + 2.
%e n 1 2 3 4 5 6 7
%e k 4 17 38 41 48 56 57
%e p(n) 7 59 163 179 223 263 269
%t t = Select[2 + Range[1440],
%t Prime[#] - Prime[# - 1] == Prime[# - 1] - Prime[# - 2] &] (* A356347 *)
%t Prime[t] (* A181424 *)
%Y Cf. A064113, A358528, A358529, A358530, A358531, A181424.
%K nonn,easy
%O 1,1
%A _Clark Kimberling_, Nov 21 2022