OFFSET
0,4
LINKS
Andrew Howroyd, Table of n, a(n) for n = 0..200
FORMULA
Moebius transform of A327868.
EXAMPLE
The a(4) = 6 primitive periodic palindromes are:
1122, 1112, 1222,
1213, 1232, 1323.
PROG
(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)}
CROSSREFS
KEYWORD
nonn
AUTHOR
Andrew Howroyd, Sep 28 2019
STATUS
approved