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 A373359 #23 Jun 22 2024 18:22:43 %S A373359 1,2,3,2,3,4,2,4,3,4,5,2,5,3,5,4,5,3,4,5,6,2,6,3,6,4,6,3,4,6,5,6,3,5, %T A373359 6,4,5,6,7,2,7,3,7,4,7,3,4,7,5,7,3,5,7,4,5,7,6,7,3,6,7,4,6,7,5,6,7,4, %U A373359 5,6,7,8,2,8,3,8,4,8,3,4,8,5,8,3,5,8,4,5,8,6,8 %N A373359 Irregular triangle read by rows where row n lists (in increasing order) the elements of the Schreier set encoded by A371176(n). %C A373359 See A373345 (where elements in each set are listed in decreasing order) for more information. %H A373359 Paolo Xausa, <a href="/A373359/b373359.txt">Table of n, a(n) for n = 1..10000</a> (rows 1..2261 of the triangle, flattened). %H A373359 Alistair Bird, <a href="https://outofthenormmaths.wordpress.com/2012/05/13/jozef-schreier-schreier-sets-and-the-fibonacci-sequence/">Jozef Schreier, Schreier sets and the Fibonacci sequence</a>, Out Of The Norm blog, May 13 2012. %F A373359 T(n,k) = A373579(n,k) - 1. %e A373359 Triangle begins: %e A373359 Corresponding Schreier %e A373359 n A371176(n) bin(A371176(n)) set (this sequence) %e A373359 ------------------------------------------------------- %e A373359 1 1 1 {1} %e A373359 2 2 10 {2} %e A373359 3 4 100 {3} %e A373359 4 6 110 {2, 3} %e A373359 5 8 1000 {4} %e A373359 6 10 1010 {2, 4} %e A373359 7 12 1100 {3, 4} %e A373359 8 16 10000 {5} %e A373359 9 18 10010 {2, 5} %e A373359 10 20 10100 {3, 5} %e A373359 11 24 11000 {4, 5} %e A373359 12 28 11100 {3, 4, 5} %e A373359 ... %t A373359 Join[{{1}}, Map[PositionIndex[Reverse[IntegerDigits[#, 2]]][1] &, Select[Range[2, 200, 2], DigitCount[#, 2, 1] <= IntegerExponent[#, 2] + 1 &]]] %Y A373359 Cf. A371176, A373345, A373558, A373579. %Y A373359 Cf. A007895 (conjectured row lengths), A373346 (row sums), A373347. %K A373359 nonn,tabf,easy,base %O A373359 1,2 %A A373359 _Paolo Xausa_, Jun 04 2024