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A319712
Sum of A034968(d) over divisors d of n, where A034968 gives the sum of digits in factorial base.
4
1, 2, 3, 4, 4, 5, 3, 6, 6, 8, 5, 9, 4, 7, 10, 10, 6, 11, 5, 14, 10, 11, 7, 12, 6, 7, 9, 12, 5, 17, 4, 13, 11, 11, 11, 18, 5, 10, 11, 21, 7, 19, 6, 18, 19, 14, 8, 18, 6, 13, 12, 13, 6, 17, 12, 18, 12, 11, 7, 29, 6, 10, 19, 19, 14, 23, 7, 19, 16, 25, 9, 24, 5, 10, 17, 17, 13, 19, 6, 30, 15, 14, 8, 31, 15, 13, 14, 27, 9, 35, 13, 23, 14, 17, 17
OFFSET
1,2
COMMENTS
Inverse Möbius transform of A034968.
FORMULA
a(n) = Sum_{d|n} A034968(d).
a(n) = A319711(n) + A034968(n).
MATHEMATICA
d[n_] := Module[{k = n, m = 2, s = 0, r}, While[{k, r} = QuotientRemainder[k, m]; k != 0 || r != 0, s += r; m++]; s]; a[n_] := DivisorSum[n, d[#] &]; Array[a, 100] (* Amiram Eldar, Feb 14 2024 *)
PROG
(PARI)
A034968(n) = { my(s=0, b=2, d); while(n, d = (n%b); s += d; n = (n-d)/b; b++); (s); };
A319712(n) = sumdiv(n, d, A034968(d));
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, Oct 02 2018
STATUS
approved