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 A104419 #4 Mar 30 2012 17:26:11 %S A104419 1,2,3,4,5,6,8,12,13,16,19,21,24,25,31,32,35,36,43,44,45,46,47,49,51, %T A104419 52,53,57,58,59,61,62,67,69,72,77,83,84,85,91,94,99,115,116,118,125, %U A104419 129,133,142,146,162,166,167,168,188,192,194,195,196 %N A104419 Numbers n such that n, p[n], p[n]+n, p[n]-n and p[n]*n all are 0-less. %e A104419 n=8 is OK because 8, p[8]=19, 19+8=27, 19-8=11, 19*8=152 all are 0-less; n=7 is not because p[7]-7=17-7=10 is not 0-less. %t A104419 id[x_]:=IntegerDigits[x];pr[i_]:=Prime[i];ra=Range[200];A104419=Select[ra, Union[id[ # ], id[pr[ # ]], id[pr[ # ]+# ], id[pr[ # ]-# ], id[pr[ # ]*# ]][[1]]!=0&] %K A104419 nonn,base %O A104419 1,2 %A A104419 _Zak Seidov_, Mar 07 2005