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.
%I A113758 #8 Mar 22 2017 03:35:15 %S A113758 10001,12,40,32,240,3040,2240,1152,6400,12800,21504,440320,2140160, %T A113758 172032,4710400,1802240,1327104,20316160,40632320,17301504,152043520, %U A113758 602931200,138412032,117440512,3607101440,1132462080,51204063232,3355443200,35232153600,202400333824,102005473280 %N A113758 a(n) is the least number having sum of digits n in base 10 and also exactly n prime factors (counted with multiplicity). %e A113758 a(2)=10001 since 1+0+0+0+1=2 and 10001=73*137 has 2 prime factors. %e A113758 a(3)=12 since 1+2=3 and 12=2*2*3 has 3 prime factors. %t A113758 Lk[n_] := Block[{k = 2}, While[n != Plus @@ IntegerDigits[k] || n != Plus @@ (Transpose[FactorInteger@k][[2]]), k++ ]; k]; L = {}; Do[v = Lk[n]; Print[{n, v}]; AppendTo[L, v], {n, 2, 13}]; L %Y A113758 Cf. A115156. %K A113758 base,nonn %O A113758 2,1 %A A113758 _Giovanni Resta_, Jan 18 2006 %E A113758 a(23)-a(28) from _Donovan Johnson_, Nov 15 2009 %E A113758 a(29)-a(32) from _Giovanni Resta_, Mar 21 2017