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 A345101 #17 Jun 10 2021 15:44:26 %S A345101 0,1,2,3,4,5,6,8,7,9,10,11,12,16,13,17,14,18,15,19,20,21,22,24,32,23, %T A345101 25,33,26,34,27,28,35,36,29,37,30,38,40,31,39,41,42,43,44,48,64,45,49, %U A345101 65,46,50,66,47,51,52,67,68,53,69,54,56,70,72,55,57,71,73 %N A345101 Irregular triangle T(n, k) read by rows, n >= 0, k = 1..A000119(n); the n-th row contains the numbers m such that A022290(m) = n, in increasing order. %C A345101 When interpreted as a flat sequence, yields a permutation of the nonnegative integers. %H A345101 Rémy Sigrist, <a href="/A345101/b345101.txt">Table of n, a(n) for n = 0..10922</a> %H A345101 Rémy Sigrist, <a href="/A345101/a345101.gp.txt">PARI program for A345101</a> %H A345101 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %F A345101 T(n, 1) = A003754(n+1). %F A345101 T(n, A000119(n)) = A003714(n). %e A345101 Triangle begins: %e A345101 0 [0] %e A345101 1 [1] %e A345101 2 [2] %e A345101 3 [3, 4] %e A345101 4 [5] %e A345101 5 [6, 8] %e A345101 6 [7, 9] %e A345101 7 [10] %e A345101 8 [11, 12, 16] %e A345101 9 [13, 17] %e A345101 10 [14, 18] %e A345101 11 [15, 19, 20] %e A345101 12 [21] %o A345101 (PARI) See Links section. %Y A345101 Cf. A000119 (row lengths), A003714, A003754, A022290. %K A345101 nonn,look,tabf %O A345101 0,3 %A A345101 _Rémy Sigrist_, Jun 08 2021