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A190727
Product of (digits of n each incremented by 1) - 2.
0
0, 1, 2, 3, 4, 5, 6, 7, 8, 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 1, 4, 7, 10, 13, 16, 19, 22, 25, 28, 2, 6, 10, 14, 18, 22, 26, 30, 34, 38, 3, 8, 13, 18, 23, 28, 33, 38, 43, 48, 4, 10, 16, 22, 28, 34, 40, 46, 52, 58, 5, 12, 19, 26, 33, 40, 47, 54, 61, 68, 6, 14, 22, 30, 38, 46, 54, 62
OFFSET
1,3
COMMENTS
Number of numbers in range 1 to n-1 whose decimal expansion is, term-by-term, dominated by n.
EXAMPLE
a(23) = 10 since all the numbers 22, 21, 20, 13, 12, 11, 10, 3, 2, 1 count.
MATHEMATICA
f[n_]:=Module[{idnp=IntegerDigits[n]+1}, Times@@idnp-2]; Array[f, 80](* Harvey P. Dale, May 24 2011 *)
PROG
(PARI) a(n) = vecprod(apply(x->x+1, digits(n))) - 2; \\ Michel Marcus, Oct 06 2021
CROSSREFS
Equals A089898(n)-2.
Sequence in context: A309788 A326746 A257849 * A195832 A265523 A004184
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, May 17 2011
STATUS
approved