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First differences of A002960.
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%I #19 Aug 12 2016 06:21:40

%S 3,3,4,5,5,6,6,7,7,8,9,9,10,10,11,11,12,12,13,13,14,14,15,15,16,17,17,

%T 18,18,19,19,20,20,21,21,22,22,23,23,24,24,25,25,26,26,27,27,28,28,29,

%U 29,30,30,31,31,32,33,33,34,34,35,35

%N First differences of A002960.

%C The squared sieve sequence (A002960) increases by one, beginning with three, every two integers except a difference of 2^n appears only once. This is the sequence of first differences. This has not yet been proven in the general case.

%F Conjecture: a(n) = A274089(n+2). - _Omar E. Pol_, Aug 10 2016

%t Rest@ Differences@ Map[First, NestWhileList[Function[w, {First@ #, Rest@ #} &@ Delete[Last@ w, #] &@ Map[{#} &, Reverse@ Range[Floor@ Sqrt@ Length[Last@ w]]^2]], {0, Range@ 1200}, Length@ Last@ # > 1 &]] (* _Michael De Vlieger_, Aug 10 2016 *)

%Y Cf. A002960, A274089.

%K nonn

%O 1,1

%A _Alisa Ediger_, Jun 06 2016