login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A190997 Product of digits of all the divisors of n. 4
1, 2, 3, 8, 5, 36, 7, 64, 27, 0, 1, 288, 3, 56, 75, 384, 7, 2592, 9, 0, 42, 8, 6, 18432, 50, 72, 378, 3584, 18, 0, 3, 2304, 27, 168, 525, 373248, 21, 432, 243, 0, 4, 16128, 12, 512, 13500, 288, 28, 3538944, 252, 0, 105, 2880, 15, 725760, 125, 860160, 945 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Product of digits of concatenation of all divisors of n (A037278).
LINKS
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
Sequence in context: A117987 A091136 A140651 * A184392 A007955 A324502
KEYWORD
nonn,easy,base
AUTHOR
Jaroslav Krizek, Jun 15 2011
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 7 17:41 EDT 2024. Contains 372312 sequences. (Running on oeis4.)