A358993 - OEIS

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A358993

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

1, 1, 1, 2, 3, 3, 4, 6, 7, 9, 10, 12, 12, 13, 15, 18, 17, 20, 21, 22, 24, 25, 27, 29, 31, 32, 34, 34, 35, 40, 40, 45, 45, 45, 46, 47, 46, 52, 55, 55, 59, 58, 60, 59, 66, 66, 65, 69, 70, 74, 80, 79, 84, 75, 83, 90, 89, 87, 92, 95, 91, 95, 104, 98, 102, 110, 107

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,4

LINKS

Table of n, a(n) for n=0..66.

FORMULA

a(n) = A055640(A358990(n)).

MATHEMATICA

Table[Length[Select[IntegerDigits[Product[2i+2Floor[(i-3)/4]+1, {i, n}]], Positive]], {n, 0, 66}]

CROSSREFS

Cf. A045572, A055640, A356861, A358990.

Cf. A358991 (number of zero digits), A358992 (number of digits).