# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a152888 Showing 1-1 of 1 %I A152888 #15 Aug 14 2013 02:22:55 %S A152888 0,2,5,9,14,21,28,36,45,55,66,77,90,104,119,135,152,170 %N A152888 Partial sums of length of terms in A081368 where A081368(1) is set to 0. %C A152888 Previous name was: The sequence of powers necessary to reconstruct Exp[0] from Thanh Diep's sequence A081368: E=Sum[A081368[n]/10^a(n),{n,1,Length}]. %D A152888 C. Pickover, Mazes for the Mind, St. Martin's Press, NY, 1992, p. 350-351. %t A152888 a = {2, 71, 828, 1828, 45904, 5235360, 2874713, 52662497, 757247093, 6999595749, 66967627724, 76630353547, 5945713821785, 25166427427466, 391932003059921, 8174135966290435, 72900334295260595, 630738132328627943}; %t A152888 b = Table[Length[IntegerDigits[a[[n]]]], {n, 1, Length[a]}]; %t A152888 c = Table[Sum[b[[m]], {m, 1, n}] - 1, {n, 1, Length[b]}] Sum[a[[n]]/10^(c[[n]]), {n, 1, Length[a]}]; %t A152888 N[% - E, 100] %o A152888 (PARI) v=[71, 828, 1828, 45904, 5235360, 2874713, 52662497, 757247093, 6999595749, 66967627724, 76630353547, 5945713821785, 25166427427466, 391932003059921, 8174135966290435, 72900334295260595, 630738132328627943]; %o A152888 concat([0],vector(#v,n,sum(j=1,n,#digits(v[j])))) \\ _Joerg Arndt_, Aug 13 2013 %K A152888 nonn,base,less %O A152888 1,2 %A A152888 _Roger L. Bagula_, Dec 14 2008 %E A152888 Edited by _Joerg Arndt_ and _Michel Marcus_, Aug 13 2013 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE