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A324341
If 2n = 2^e1 + ... + 2^ek [e1 .. ek distinct], then a(n) is the number of nonzero digits when A002110(e1) * ... * A002110(ek) is written in primorial base.
6
1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 2, 2, 3, 3, 1, 1, 1, 1, 2, 2, 2, 3, 2, 3, 3, 3, 4, 2, 2, 3, 1, 1, 1, 1, 2, 2, 2, 3, 2, 3, 3, 3, 3, 3, 3, 4, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 5, 4, 6, 6, 6, 6, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5
OFFSET
0,8
COMMENTS
Number of nonzero digits when A283477(n) is represented in primorial base, A049345.
Number of distinct prime factors in A324289(n).
FORMULA
a(n) = A267263(A283477(n)).
a(n) <= A324342(n).
PROG
(PARI)
A002110(n) = prod(i=1, n, prime(i));
A030308(n, k) = bittest(n, k);
A283477(n) = prod(i=0, #binary(n), if(0==A030308(n, i), 1, A030308(n, i)*A002110(1+i)));
A267263(n) = { my(s=0); forprime(p=2, , if(n%p, s++, if(n==0, return(s))); n\=p); }; \\ From A267263
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 23 2019
STATUS
approved