OFFSET
1,2
COMMENTS
Product of digits of concatenation of all divisors of n (A037278).
LINKS
Nathaniel Johnston, Table of n, a(n) for n = 1..10000
FORMULA
a(n) = 0 for n = multiples of 10; a(A008592(n)) = 0 for n >=1.
EXAMPLE
For n = 12: a(12) = 1 * 2 * 3 * 4 * 6 * 1 * 2 = 288.
MAPLE
A190997:=proc(n) local d, i, p: d:=numtheory[divisors](n): p:=1: for i from 1 to nops(d) do p:=p*mul(d, d=convert(d[i], base, 10)): od: return p: end: seq(A190997(n), n=1..57); # Nathaniel Johnston, Jun 15 2011
MATHEMATICA
Table[Times@@Flatten[IntegerDigits/@Divisors[n]], {n, 100}] (* Harvey P. Dale, Nov 27 2022 *)
PROG
(PARI) a007954(n) = my(d=digits(n)); prod(i=1, #d, d[i]);
a(n) = my(div=divisors(n), pdt=1); for(k=1, #div, pdt=pdt*a007954(div[k])); pdt \\ Felix Fröhlich, Sep 22 2016
CROSSREFS
KEYWORD
nonn,easy,base
AUTHOR
Jaroslav Krizek, Jun 15 2011
STATUS
approved