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 A236429 Number of representations of 0 as a sum of numbers d*k with d in {-1,1} and k in {1,2,...,n}, where the sum of the numbers k is 2n. 1
 1, 3, 6, 14, 25, 52, 86, 160, 260, 443, 688, 1146, 1721, 2716, 4040, 6176, 8975, 13482, 19218, 28167, 39799, 57081, 79503, 112987, 155368 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(n) = number of partitions of 2n that contain a partition of n. LINKS EXAMPLE a(3) counts these 6 representations of 0: 3-3, 3-2-1, 3-1-1-1, 2+1-2-1, 2+1-1-1-1, 1+1+1-1-1-1. MATHEMATICA p[n_] := p[n] = IntegerPartitions[n]; Map[({p1 = p[#], p2 = p[2 #]} &[#];    Length[Cases[p2, Apply[Alternatives, Map[Flatten[{___, #, ___}] &, p1]]]]) &,  Range[12]] Map[({p1 = p[# + 1], p2 = p[2 # + 1]} &[#]; Length[Cases[p2, Apply[Alternatives, Map[Flatten[{___, #, ___}] &, p1]]]]) &, Range[12]] (* Peter J. C. Moses, Jan 04 2014 *) CROSSREFS Cf. A236430, A235130. Sequence in context: A166212 A291988 A285460 * A316245 A002219 A006906 Adjacent sequences:  A236426 A236427 A236428 * A236430 A236431 A236432 KEYWORD nonn,more AUTHOR Clark Kimberling, Jan 25 2014 STATUS approved

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Last modified December 12 03:27 EST 2018. Contains 318052 sequences. (Running on oeis4.)