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%I #13 Jul 16 2018 12:34:28
%S 1,2,8,9,12,15,24,25,28,45,54,85,111,112,128,133,153,165,192,198,228,
%T 288,294,312,342,416,432,448,481,527,528,638,828,891,1115,1127,1134,
%U 1176,1215,1224,1245,1278,1344,1431,1472,1482,1519,1652,1674,1976,2114,2147,2178,2184
%N Numbers with decimal expansion d_1,d_2,...,d_k that are divisible by sigma_0(d_k) + sigma_1(d_k-1) + ... + sigma_k-1(d_1).
%C sigma_k(n) is the sum of the k-th powers of the divisors of n.
%H Harvey P. Dale, <a href="/A289146/b289146.txt">Table of n, a(n) for n = 1..1000</a>
%e 25 is in the sequence as 25 is divisible by sigma_0(5) + sigma_1(2) = 2 + 3 = 5.
%t f[n_]:=Reverse[IntegerDigits[n]];
%t g[n_]:=Sum[DivisorSigma[i-1,f[n][[i]]],{i,1,Length[f[n]]}];
%t Select[Range[10000],Divisible[#,g[#]]&]
%t ds[n_]:=Total[DivisorSigma[#[[2]],#[[1]]]&/@Thread[{IntegerDigits[ n], Range[ IntegerLength[n]-1,0,-1]}]]; Select[Range[3000],Divisible[ #, ds[#]]&] (* _Harvey P. Dale_, Jul 16 2018 *)
%o (PARI) isok(n) = my(d = Vecrev(digits(n))); if (vecmin(d), n % sum(k=1, #d, sigma(d[k], k-1)) == 0); \\ _Michel Marcus_, Jun 26 2017
%Y Subsequence of A052382.
%K base,nonn
%O 1,2
%A _Ivan N. Ianakiev_, Jun 26 2017
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