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%I #5 Oct 20 2014 14:44:35
%S 1,2,3,4,5,7,6,8,9,31,10,11,12,27,28,14,16,63,17,18,19,20,32,21,22,23,
%T 127,24,25,26,29,115,30,33,34,35,36,37,38,39,40,111,41,255,42,43,44,
%U 45,46,47,48,49,50,51,52,53,54,56,58,59,60,61,62,64,66,67
%N a(n) = index of (n+1)-th prime power in A247665.
%o (Haskell)
%o import Data.List (elemIndex); import Data.Maybe (fromJust)
%o a248918 = (+ 1) . fromJust . (`elemIndex` a247665_list) . a000961 . (+ 1)
%Y Cf. A248387 (subsequence), A000961.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Oct 16 2014
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