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 A143707 #5 Mar 30 2012 18:52:27 %S A143707 5,14,20,12,14,44,45,56,42,10,76,50,68,12,20,78,18,145,165,70,44,28, %T A143707 117,44,65,215,150,26,21,140,14,28,25,68,715,24,55,154,176,10,315,155, %U A143707 56,75,234,38,75,390,12,150,296,8,342,32,474,35,248,10,154,92,145,1001,21,105 %N A143707 (1, 2, 3, 2^2, 5, 2*3, 7, 2^3, 3^2, 2*5, 11, 2^2*3, 13, 2*7, 3*5,..) becomes (1*(2+3), 2*(2+5), 2*(3+7), 2*(3+3), 2*(2+5), 11*(2+2), 3*(13+2), 7*(3+5),..). %e A143707 a(8)=7*(3+5)=7*8=56. %e A143707 a(9)=2*(4+17)=2*21=42. %e A143707 a(10)=2*(3+2)=2*5=10. %e A143707 a(11)=19*(2+2)=19*4=40. %e A143707 a(12)=5*(3+7)=5*10=50. %e A143707 a(13)=2*(11+23)=2*34=68, %e A143707 etc. %Y A143707 Cf. A141287, A141261, A136735. %K A143707 nonn %O A143707 1,1 %A A143707 _Juri-Stepan Gerasimov_, Nov 13 2008 %E A143707 Corrected (40 replaced by 76, 18 by 12, 90 by 70 etc.) by _R. J. Mathar_, Apr 18 2010