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A238781
Number of palindromic partitions of n whose least part has multiplicity 1.
4
1, 1, 1, 1, 2, 1, 2, 2, 3, 2, 4, 2, 6, 4, 6, 4, 10, 5, 12, 7, 16, 8, 20, 10, 27, 14, 32, 16, 44, 19, 53, 25, 69, 31, 84, 36, 108, 47, 130, 55, 167, 67, 202, 83, 252, 99, 305, 119, 380, 146, 456, 173, 564, 208, 676, 250, 826, 298, 991, 352, 1205, 424, 1435
OFFSET
1,5
COMMENTS
Palindromic partitions are defined at A025065.
EXAMPLE
a(11) counts these partitions (written as palindromes): [11], [5,1,5], [4,3,4], [2,3,1,3,2].
MATHEMATICA
z = 40; p[n_, k_] := Select[IntegerPartitions[n], (Count[OddQ[Transpose[Tally[#]][[2]]], True] <= 1) && (Count[#, Min[#]] == k) &]
Table[p[n, 1], {n, 1, 12}]
t1 = Table[Length[p[n, 1]], {n, 1, z}] (* A238781 *)
Table[p[n, 2], {n, 1, 12}]
t2 = Table[Length[p[n, 2]], {n, 1, z}] (* A238782 *)
Table[p[n, 3], {n, 1, 12}]
t3 = Table[Length[p[n, 3]], {n, 1, z}] (* A238783 *)
Table[p[n, 4], {n, 1, 12}]
t4 = Table[Length[p[n, 4]], {n, 1, z}] (* A238784 *)
(* Peter J. C. Moses, Mar 03 2014 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Mar 05 2014
STATUS
approved