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 A173991 #11 Apr 18 2013 06:30:38 %S A173991 1,2,6,7,5,8,4,9,3,10,14,15,13,16,12,17,11,18,27,28,26,29,25,30,24,31, %T A173991 23,32,22,33,21,34,20,35,19,36,45,46,44,47,43,48,42,49,41,50,40,51,39, %U A173991 52,38,53,37,54,70,71,69,72,68,73,67,74,66,75,65,76,64,77,63,78,62,79 %N A173991 Bayley-Thomsen-Bohr periodic table(s) (1882-1895-1922) adapted by Scerri (1997). %C A173991 This a compact (no spaces) symmetric table of (7 rows, 32 columns) 118 elements. Also from Mendeleyev-Moseley-Seaborg. A permutation of the numbers from 1 to 118. The writing is the same as A172002, from Janet table. %C A173991 Writing begins from central (two) columns. Number of terms by columns: 2,2,2,2,2,2,2,4,4,4,4,4,6,6,6,7,7,6,6,6,4,4,4,4,4,2,2,2,2,2,2,2; by rows: 2,8,8,18,18,32,32 (see A093907 and A137583). %F A173991 a(n)= A172002(n+2) - 2. %K A173991 nonn,fini,tabf %O A173991 1,2 %A A173991 _Paul Curtz_, Mar 04 2010