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A319468
Number of partitions of n into exactly two nonzero decimal palindromes.
6
0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 4, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1
OFFSET
0,5
LINKS
FORMULA
a(n) = [x^n y^2] 1/Product_{j>=2} (1-y*x^A002113(j)).
a(n) = 0 <=> n in { A319477 }.
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`(t*i<n,
0, b(n, h(i-1), t)+b(n-i, h(min(n-i, i)), t-1)))
end:
a:= n-> (k-> b(n, h(n), k)-b(n, h(n), k-1))(2):
seq(a(n), n=0..100);
CROSSREFS
Column k=2 of A319453.
Sequence in context: A336430 A368086 A167232 * A137791 A351834 A096125
KEYWORD
nonn,look,base
AUTHOR
Alois P. Heinz, Sep 19 2018
STATUS
approved