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A340197
a(1) = 1; for n > 1, a(n) = Sum_{d|n, d<n} (A318833(n/d)-1) * A340197(d).
5
1, 0, 0, 2, 0, 7, 0, 6, 6, 13, 0, 13, 0, 19, 22, 18, 0, 19, 0, 23, 32, 31, 0, 53, 20, 37, 24, 33, 0, 21, 0, 54, 52, 49, 58, 110, 0, 55, 62, 95, 0, 29, 0, 53, 52, 67, 0, 185, 42, 53, 82, 63, 0, 139, 94, 137, 92, 85, 0, 321, 0, 91, 74, 162, 112, 45, 0, 83, 112, 45, 0, 403, 0, 109, 82, 93, 136, 53, 0, 331, 114, 121
OFFSET
1,4
COMMENTS
See comments and question in A340140.
LINKS
FORMULA
a(1) = 1; for n > 1, a(n) = Sum_{d|n, d<n} (A318833(n/d)-1) * A340197(d).
PROG
(PARI)
A023900(n) = factorback(apply(p -> 1-p, factor(n)[, 1]));
A318833(n) = (n+A023900(n));
A340197(n) = if(1==n, 1, sumdiv(n, d, if(d<n, (A318833(n/d)-1)*A340197(d), 0)));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 05 2021
STATUS
approved