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A079099
Number of 0's in n primorial or 0's in A002110(n).
10
0, 0, 0, 1, 1, 1, 3, 2, 1, 2, 1, 5, 2, 3, 4, 1, 3, 4, 3, 5, 4, 5, 4, 3, 5, 4, 8, 2, 3, 3, 6, 6, 7, 12, 12, 6, 6, 5, 9, 7, 8, 7, 7, 10, 9, 5, 9, 7, 9, 10, 17, 12, 11, 16, 16, 13, 10, 10, 14, 11, 14, 9, 16, 11, 14, 8, 13, 16, 14, 4, 15, 15, 17, 9, 19, 15, 17, 17, 22, 15, 12, 19, 14, 18, 11, 21, 19, 18, 19, 22, 15
OFFSET
0,7
COMMENTS
The sum of the reciprocals appear to converge.
LINKS
MAPLE
p:= proc(n) option remember; `if`(n<1, 1, p(n-1)*ithprime(n)) end:
a:= n-> nops([StringTools[SearchAll]("0", ""||(p(n)))]):
seq(a(n), n=0..90); # Alois P. Heinz, Jul 21 2025
MATHEMATICA
DigitCount[#, 10, 0]&/@FoldList[Times, Prime[Range[90]]] (* Harvey P. Dale, Mar 05 2022 *)
PROG
(PARI) a(n, dg=0) = { my(y=vecprod(primes(n))); #select(x->x==dg, digits(y)) }
CROSSREFS
Sequence in context: A254629 A096248 A079109 * A213195 A256794 A366899
KEYWORD
nonn,base,easy
AUTHOR
Cino Hilliard, Feb 03 2003
EXTENSIONS
Offset corrected by Alois P. Heinz, Jul 21 2025
STATUS
approved