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%I A081751 #9 Nov 27 2014 04:07:54
%S A081751 12,24,78,66,54,42,30,120,540,390,264,282,366,180,546,510,330,318,990,
%T A081751 936,702,780,564,1290,870,528,312,168,222,150,138,5778,6174,3432,3150,
%U A081751 2850,2190,8432,4464,3472,2480,1488,5430,6750,4452,4396,4650,3270,2712
%N A081751 a(n) is the smallest number that is precisely n-tuply abundant.
%C A081751 See A081705 for the definition of n-tuply abundant. - _David Wasserman_, Jun 24 2004
%e A081751 a(3)=78 because 78 is the smallest number that is exactly triply abundant, with this aliquot chain: 78->90->144->259->45.
%o A081751 (PARI) LIMIT = 50; A = vector(LIMIT); count = 0; i = 1; while (count < LIMIT, i = i + 1; ab = 0; lastn = i; n = sigma(i) - i; while(ab <= LIMIT && n > lastn, ab = ab + 1; lastn = n; n = sigma(lastn) - n); if(ab <= LIMIT && ab > 0 && A[ab] == 0, A[ab] = i; count = count + 1)); A \\ _David Wasserman_, Jun 24 2004
%Y A081751 Cf. A081705, A081699.
%K A081751 nonn
%O A081751 1,1
%A A081751 Gabriel Cunningham (gcasey(AT)mit.edu), Apr 08 2003
%E A081751 More terms from _David Wasserman_, Jun 24 2004

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