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%I #7 Feb 07 2021 13:10:15
%S 1,3,6,10,15,21,28,36,45,52,60,66,70,72,72,70,66,60,55,45,39,34,30,27,
%T 25,24,24,24,27,27,25,27,27,27,27,27,27,27,27,30,27,27,30,30,30,30,30,
%U 30,30,30,33,27,30,33,33,33,33,33,33,33,33,36,27,34,36,36,36,36
%N Number of ways to write n as an ordered sum of 3 nonzero decimal palindromes.
%H Alois P. Heinz, <a href="/A341192/b341192.txt">Table of n, a(n) for n = 3..20000</a>
%t nmax = 70; CoefficientList[Series[Sum[Boole[PalindromeQ[k]] x^k, {k, 1, nmax}]^3, {x, 0, nmax}], x] // Drop[#, 3] &
%Y Cf. A002113, A136522, A261131, A261132, A261422, A341156, A341191, A341193.
%K nonn,base
%O 3,2
%A _Ilya Gutkovskiy_, Feb 06 2021
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