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A238791 Number of palindromic partitions of n such that the multiplicities of the least and greatest parts are equal. 2
1, 2, 2, 3, 2, 5, 2, 5, 3, 7, 2, 11, 3, 10, 6, 15, 5, 22, 7, 28, 12, 33, 15, 52, 21, 59, 33, 84, 38, 112, 56, 145, 77, 178, 103, 251, 132, 300, 184, 404, 229, 507, 304, 645, 398, 800, 506, 1040, 639, 1270, 832, 1608, 1032, 1988, 1310, 2479, 1640, 3031, 2053 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Palindromic partitions are defined at A025065.

LINKS

Table of n, a(n) for n=1..59.

EXAMPLE

a(10) counts these 7 partitions (written as palindromes):  [10], [5,5], [1,4,4,1], [2,3,3,2], [1,3,2,3,1], [2,2,2,2,2], 1,1,1,1,1,1,1,1,1,1].

MATHEMATICA

z = 40; p[n_] := p[n] = Select[IntegerPartitions[n], (Count[OddQ[Transpose[Tally[#]][[2]]], True] <= 1) && (Count[#, Min[#]] == Count[#, Max[#]]) &]; Table[p[n], {n, 1, 12}]

Table[Length[p[n]], {n, 1, z}]

CROSSREFS

Cf. A025065, A238792, A238793, A238779.

Sequence in context: A272209 A323347 A322900 * A007012 A298423 A319810

Adjacent sequences:  A238788 A238789 A238790 * A238792 A238793 A238794

KEYWORD

nonn,easy

AUTHOR

Clark Kimberling, Mar 05 2014

STATUS

approved

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Last modified April 24 16:16 EDT 2019. Contains 322430 sequences. (Running on oeis4.)