cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A095404 Numbers n such that Sum-of-digits-of-n > Sum-of-digits-of-all-distinct-prime-factors-of-n.

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%I A095404 #5 Oct 15 2013 22:32:25
%S A095404 1,4,6,8,9,16,18,24,25,26,27,28,32,33,36,39,44,45,46,48,49,52,54,55,
%T A095404 56,62,64,65,66,68,69,72,75,76,77,78,80,81,82,86,87,88,92,93,96,98,99,
%U A095404 108,117,121,124,125,128,129,135,138,143,144,147,148,155,156,159,162,164
%N A095404 Numbers n such that Sum-of-digits-of-n > Sum-of-digits-of-all-distinct-prime-factors-of-n.
%F A095404 Solutions to A007953[x]>A095402[x].
%e A095404 n=24: digit sum=6, prime factor-digit sum=2+3=5, so 24 is here;
%e A095404 n=153: digit sum=9, prime factor-digit sum=3+5+3=11>9, so 153 is here.
%t A095404 ffi[x_] :=Flatten[FactorInteger[x]] lf[x_] :=Length[FactorInteger[x]] ba[x_] :=Table[Part[ffi[x], 2*j-1], {j, 1, lf[x]}] sd[x_] :=Apply[Plus, IntegerDigits[x]] tdp[x_] :=Flatten[Table[IntegerDigits[Part[ba[x], j]], {j, 1, lf[x]}], 1] sdp[x_] :=Apply[Plus, tdp[x]] a=Table[sd[w], {w, 1, 256}];b=Table[sdp[w], {w, 1, 150}];b-a; Flatten[Position[Sign[b-a], 1]]
%Y A095404 Cf. A007953, A051351, A095402, A095403, A095405, A095406.
%K A095404 nonn,base
%O A095404 1,2
%A A095404 _Labos Elemer_, Jun 21 2004