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%I #12 Nov 29 2015 12:40:59
%S 12,12,12,12,20,12,42,24,18,20,66,12,78,42,30,48,102,18,114,20,42,66,
%T 138,24,100,78,54,56,174,30,186,96,66,102,70,36,222,114,78,40,246,42,
%U 258,88,90,138,282,48,196,100,102,104,318,54,220,56,114,174,354,60,366
%N Least abundant number divisible by n.
%H Harry J. Smith, <a href="/A064162/b064162.txt">Table of n, a(n) for n=1..1000</a>
%e The first eight abundant numbers are 12, 18, 20, 24, 30, 36, 40 and 42. But only the last one is divisible by 7. Therefore a(7) = 42.
%t Do[ k = 11; While[ m = DivisorSigma[ 1, k ] - 2k; m <= 0 || Mod[ k, n ] != 0, k++ ]; Print[ k ], {n, 1, 75} ]
%t With[{abnos=Select[Range[500],DivisorSigma[1,#]>2#&]},Table[ SelectFirst[ abnos, Divisible[ #,n]&],{n,70}]] (* The program uses the SelectFirst function from Mathematica version 10 *) (* _Harvey P. Dale_, Nov 29 2015 *)
%o (PARI) { for (n=1, 1000, k=11; until (sigma(k) - k > k && k%n == 0, k++); write("b064162.txt", n, " ", k) ) } \\ _Harry J. Smith_, Sep 09 2009
%K easy,nonn
%O 1,1
%A _Robert G. Wilson v_, Sep 15 2001