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%I #19 Nov 27 2022 18:57:42
%S 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,
%T 72,378,3584,18,0,3,2304,27,168,525,373248,21,432,243,0,4,16128,12,
%U 512,13500,288,28,3538944,252,0,105,2880,15,725760,125,860160,945
%N Product of digits of all the divisors of n.
%C Product of digits of concatenation of all divisors of n (A037278).
%H Nathaniel Johnston, <a href="/A190997/b190997.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = 0 for n = multiples of 10; a(A008592(n)) = 0 for n >=1.
%e For n = 12: a(12) = 1 * 2 * 3 * 4 * 6 * 1 * 2 = 288.
%p 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
%t Table[Times@@Flatten[IntegerDigits/@Divisors[n]],{n,100}] (* _Harvey P. Dale_, Nov 27 2022 *)
%o (PARI) a007954(n) = my(d=digits(n)); prod(i=1, #d, d[i]);
%o a(n) = my(div=divisors(n), pdt=1); for(k=1, #div, pdt=pdt*a007954(div[k])); pdt \\ _Felix Fröhlich_, Sep 22 2016
%Y Cf. A134681, A034690.
%K nonn,easy,base
%O 1,2
%A _Jaroslav Krizek_, Jun 15 2011
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