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%I #8 Oct 03 2019 20:59:45
%S 1,1,1,2,6,12,40,74,300,538,2598,4682,25938,47292,296488,545820,
%T 3816240,7087260,54666830,102247562,862437450,1622632496,14857095400,
%U 28091567594,277474931700,526858348368,5584100612118,10641342969902,120462266677578
%N Number of primitive (period n) periodic palindromes with integer entries that cover an initial interval of positive integers.
%H Andrew Howroyd, <a href="/A327879/b327879.txt">Table of n, a(n) for n = 0..200</a>
%F Moebius transform of A327868.
%e The a(4) = 6 primitive periodic palindromes are:
%e 1122, 1112, 1222,
%e 1213, 1232, 1323.
%o (PARI) a(n)={if(n<1, n==0, sumdiv(n, d, moebius(n/d)*sum(k=0, n, k!*(stirling((d+1)\2, k, 2)+stirling(d\2+1, k, 2))))/2)}
%Y Row sums of A327878.
%Y Cf. A327868, A327874.
%K nonn
%O 0,4
%A _Andrew Howroyd_, Sep 28 2019