cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A166685 Odd numbers that are the sum of two consecutive nonprimes.

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%I A166685 #12 Mar 07 2020 22:14:43
%S A166685 1,5,17,19,29,31,41,43,49,51,53,55,65,67,69,71,77,79,89,91,97,99,101,
%T A166685 103,109,111,113,115,125,127,129,131,137,139,149,151,153,155,161,163,
%U A166685 169,171,173,175,181,183,185,187,189,191,197,199,209,211,221,223,229
%N A166685 Odd numbers that are the sum of two consecutive nonprimes.
%H A166685 Harvey P. Dale, <a href="/A166685/b166685.txt">Table of n, a(n) for n = 1..1000</a>
%e A166685 a(1)=0(1st nonprime)+1(2nd nonprime)=1(odd);
%e A166685 a(2)=1(2nd nonprime)+4(3rd nonprime)=5(odd).
%t A166685 Select[Total/@Partition[Select[Range[0,200],!PrimeQ[#]&],2,1],OddQ] (* _Harvey P. Dale_, Mar 07 2020 *)
%Y A166685 Cf. A118134, A141468, A163467.
%K A166685 nonn
%O A166685 1,2
%A A166685 _Juri-Stepan Gerasimov_, Oct 18 2009
%E A166685 Entries checked by _R. J. Mathar_, Apr 24 2010