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A328766
Number of nonleading zeros in primorial base expansion of A276086(n).
4
0, 1, 0, 2, 0, 2, 0, 1, 0, 3, 0, 3, 1, 1, 0, 3, 1, 3, 1, 1, 0, 3, 0, 3, 1, 1, 0, 3, 0, 3, 1, 1, 0, 2, 1, 2, 1, 1, 0, 4, 0, 4, 1, 1, 0, 4, 0, 4, 1, 1, 0, 4, 0, 4, 1, 1, 0, 4, 1, 4, 1, 1, 0, 2, 1, 2, 1, 1, 0, 4, 0, 4, 1, 2, 0, 4, 0, 4, 1, 1, 0, 4, 0, 4, 2, 2, 1, 4, 0, 4, 1, 1, 0, 2, 0, 2, 1, 1, 0, 4, 0, 5, 1, 1, 0, 4
OFFSET
0,4
FORMULA
a(n) = A328620(A276086(n)) = A079067(A276087(n)).
a(n) = A001221(A328763(n)) - 1.
For all n >= 1, a(A143293(n-1)) = n. [Note however that these are not the first occurrences of each n, that is, A143293 does not give the indices of records]
PROG
(PARI)
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
A328620(n) = { my(s=0, p=2); while(n, s += (0==(n%p)); n = n\p; p = nextprime(1+p)); (s); };
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 28 2019
STATUS
approved