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Indices of semiprimes in A166133.
3

%I #7 Apr 14 2015 09:59:31

%S 3,7,12,11,15,14,17,24,29,28,36,35,34,31,30,47,50,52,56,58,59,63,66,

%T 25,77,74,92,89,102,101,109,107,106,105,83,116,128,125,124,143,142,

%U 141,135,131,147,154,155,156,103,171,99,96,95,145,189,259,178,177

%N Indices of semiprimes in A166133.

%H Reinhard Zumkeller and Ray Chandler, <a href="/A256563/b256563.txt">Table of n, a(n) for n = 1..10000</a> (first 1000 terms from Reinhard Zumkeller)

%F a(n) = A255833(A001358(n)). - _Ray Chandler_, Apr 14 2015

%o (Haskell)

%o a256563 = (+ 1) . fromJust . (`elemIndex` a166133_list) . a001358

%Y Cf. A166133, A256561, A255833, A001358.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Apr 02 2015