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.

A082917 Numbers that can be expressed as the sum of two odd primes in more ways than any smaller even number.

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%I A082917 #22 Jan 15 2023 00:27:35
%S A082917 6,10,22,34,48,60,78,84,90,114,120,168,180,210,300,330,390,420,510,
%T A082917 630,780,840,990,1050,1140,1260,1470,1650,1680,1890,2100,2310,2730,
%U A082917 3150,3570,3990,4200,4410,4620,5250,5460,6090,6510,6930,7980,8190,9030,9240
%N A082917 Numbers that can be expressed as the sum of two odd primes in more ways than any smaller even number.
%C A082917 The terms up to 114 are identical with A001172. The record-setting number of decompositions is given by A082918.
%C A082917 It appears that every primorial number (A002110) greater than 30 is in this sequence. Sequence A116979 gives the number of decompositions for n equal to a primorial number. - _T. D. Noe_, Mar 15 2010
%H A082917 Bill Hannaford, <a href="/A082917/b082917.txt">Table of n, a(n) for n = 1..420</a> (first 244 terms from T. D. Noe)
%e A082917 a(1) = 6 = 3 + 3.
%e A082917 a(2) = 10 because 10 is the smallest number that can be written in two ways: 10 = 3 + 7 = 5 + 5.
%t A082917 kmax = 40000;
%t A082917 ip[k_] := IntegerPartitions[k, {2}, Select[Range[3, k-1], PrimeQ]];
%t A082917 seq = Module[{k, lg, record = 0, n = 0}, Reap[For[k = 6, k <= kmax, k = k+2, lg = Length[ip[k]]; If[lg > record, record = lg; n = n+1; Print["a(", n, ") = ", k]; Sow[k]]]][[2, 1]]] (* _Jean-François Alcover_, Jun 04 2022 *)
%Y A082917 Cf. A002375, A001172, A082918. A109679 is another version of the same sequence.
%K A082917 nonn
%O A082917 1,1
%A A082917 _Hugo Pfoertner_, Apr 15 2003