A358991 a(n) is the number of zero digits in the product of the first n odd numbers not divisible by 5.

0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 2, 1, 0, 2, 1, 1, 2, 2, 3, 2, 2, 2, 3, 2, 4, 5, 2, 4, 1, 3, 4, 5, 6, 9, 5, 4, 6, 4, 7, 7, 10, 5, 7, 10, 8, 9, 8, 4, 7, 4, 15, 9, 4, 7, 12, 9, 8, 14, 12, 5, 14, 12, 6, 11, 10, 14, 17, 17, 11, 19, 11, 15, 19, 15, 13, 14, 11, 19

Offset

0,14

Links

Table of n, a(n) for n=0..80.

Formula

a(n) = A055641(A356990(n)).

Mathematica

Table[Count[IntegerDigits[Product[2i+2Floor[(i-3)/4]+1, {i, n}]], 0], {n, 0, 80}]

Crossrefs

Cf. A045572, A055641, A356859, A358990.

Cf. A358992 (number of digits), A358993 (number of nonzero digits).

Sequence in context: A190762 A025846 A241272 * A033780 A035210 A366750

Adjacent sequences: A358988 A358989 A358990 * A358992 A358993 A358994

Keyword

nonn,base

Author

Stefano Spezia, Dec 09 2022

Status

approved