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A083891 Number of divisors of n with largest digit = 4 (base 10). 11
0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 2, 0, 0, 0, 2, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 2, 1, 2, 1, 2, 0, 0, 0, 2, 0, 0, 0, 1, 0, 0, 0, 2, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 2, 0, 1, 0, 2, 0, 0, 0, 1, 0, 0, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 0, 0, 1, 0, 0, 0, 2, 0, 1, 0, 1, 0, 1, 0, 2, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,24

COMMENTS

a(n) = A000005(n) - A083888(n) - A083889(n) - A083890(n) - A083892(n) - A083893(n) - A083894(n) - A083895(n) - A083896(n) = A083899(n) - A083898(n).

LINKS

Table of n, a(n) for n=1..105.

EXAMPLE

n=120, 3 of the 16 divisors of 120 have largest digit =4:

{4,24,40}, therefore a(120)=3.

MATHEMATICA

Table[Count[Divisors[n], _?(Max[IntegerDigits[#]]==4&)], {n, 110}] (* Harvey P. Dale, Feb 19 2016 *)

CROSSREFS

Cf. A054055, A000005, A083899.

Sequence in context: A130207 A167688 A083914 * A087623 A265260 A269243

Adjacent sequences:  A083888 A083889 A083890 * A083892 A083893 A083894

KEYWORD

nonn,base

AUTHOR

Reinhard Zumkeller, May 08 2003

STATUS

approved

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Last modified January 15 20:47 EST 2019. Contains 319184 sequences. (Running on oeis4.)