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%I #16 Jan 12 2015 11:03:07
%S 1,2,4,5,8,9,10,11,12,14,16,17,18,19,20,21,22,23,24,25,26,29,30,33,34,
%T 35,36,37,38,39,41,42,43,44,45,46,47,48,49,51,52,53,54,56,58,59,60,61,
%U 62,64,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81
%N a(n) = index of n-th prime in A247665.
%H Russ Cox and N. J. A. Sloane, <a href="/A248387/b248387.txt">Table of n, a(n) for n = 1..99436</a>
%o (Haskell)
%o import Data.List (elemIndex); import Data.Maybe (fromJust)
%o a248387 = (+ 1) . fromJust . (`elemIndex` a247665_list) . a000040
%o -- _Reinhard Zumkeller_, Oct 16 2014
%Y Cf. A247665, A248388, A248379.
%Y Subsequence of A248918.
%K nonn
%O 1,2
%A _Russ Cox_ and _N. J. A. Sloane_, Oct 16 2014