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A319454 Number of partitions of 2n into exactly n nonzero decimal palindromes. 2
1, 1, 2, 3, 5, 7, 11, 15, 22, 29, 41, 53, 72, 92, 121, 153, 197, 245, 310, 381, 475, 579, 711, 858, 1043, 1248, 1501, 1783, 2126, 2507, 2966, 3476, 4083, 4757, 5551, 6433, 7464, 8606, 9931, 11398, 13089, 14957, 17099, 19461, 22153, 25120, 28483, 32183, 36361 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Alois P. Heinz, Table of n, a(n) for n = 0..1500

FORMULA

a(n) = [x^(2n) y^n] 1/Product_{j>=2} (1-y*x^A002113(j)).

a(n) = A319453(2n,n).

MAPLE

p:= proc(n) option remember; local i, s; s:= ""||n;

      for i to iquo(length(s), 2) do if

        s[i]<>s[-i] then return false fi od; true

    end:

h:= proc(n) option remember; `if`(n<1, 0,

     `if`(p(n), n, h(n-1)))

    end:

b:= proc(n, i, t) option remember; `if`(n=0, 1, `if`(i<1 or

      t<1, 0, b(n, h(i-1), t)+b(n-i, h(min(n-i, i)), t-1)))

    end:

a:= n-> `if`(n=0, 1, b(2*n, h(2*n), n)-b(2*n, h(2*n), n-1)):

seq(a(n), n=0..70);

CROSSREFS

Cf. A002113, A319453.

Sequence in context: A238866 A035978 A319475 * A023029 A035987 A035997

Adjacent sequences:  A319451 A319452 A319453 * A319455 A319456 A319457

KEYWORD

nonn,base

AUTHOR

Alois P. Heinz, Sep 19 2018

STATUS

approved

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Last modified February 21 19:31 EST 2020. Contains 332110 sequences. (Running on oeis4.)