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A324888
Minimal number of primorials (A002110) that add to A108951(n).
21
1, 1, 1, 2, 1, 2, 1, 2, 2, 2, 1, 4, 1, 2, 6, 4, 1, 4, 1, 4, 6, 2, 1, 4, 6, 2, 2, 4, 1, 6, 1, 2, 6, 2, 10, 8, 1, 2, 6, 2, 1, 2, 1, 4, 6, 2, 1, 4, 8, 12, 6, 4, 1, 4, 6, 8, 6, 2, 1, 6, 1, 2, 6, 4, 14, 12, 1, 4, 6, 10, 1, 6, 1, 2, 10, 4, 18, 12, 1, 4, 8, 2, 1, 4, 12, 2, 6, 8, 1, 12, 18, 4, 6, 2, 8, 8, 1, 16, 12, 8, 1, 12, 1, 8, 8
OFFSET
1,4
COMMENTS
Sum of digits when A108951(n) is written in primorial base (A049345).
FORMULA
a(n) = A276150(A108951(n)).
a(n) = A001222(A324886(n)).
MATHEMATICA
With[{b = Reverse@ Prime@ Range@ 120}, Array[Total@ IntegerDigits[#, MixedRadix[b]] &@ Apply[Times, Map[#1^#2 & @@ # &, FactorInteger[#] /. {p_, e_} /; e > 0 :> {Times @@ Prime@ Range@ PrimePi@ p, e}]] &, 105] ] (* Michael De Vlieger, Nov 18 2019 *)
PROG
(PARI)
A034386(n) = prod(i=1, primepi(n), prime(i));
A108951(n) = { my(f=factor(n)); prod(i=1, #f~, A034386(f[i, 1])^f[i, 2]) }; \\ From A108951
A276150(n) = { my(s=0, m); forprime(p=2, , if(!n, return(s)); m = n%p; s += m; n = (n-m)/p); };
CROSSREFS
Cf. A324383, A324386, A324387 (permutations of this sequence).
Sequence in context: A369713 A295635 A115751 * A249145 A048684 A191613
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 30 2019
STATUS
approved