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 A335547 #31 Sep 19 2020 02:22:18 %S A335547 1,2,5,18,94,709,7710,120882,2732104,89015152,4180822859,283067837700, %T A335547 27628050712667,3887236104777699,788428930992492718, %U A335547 230523466443694083587,97162501670167108808501,59035492675117768533460333,51708108674446390274283614578,65288256486029805607741923173692 %N A335547 a(n) is the number of ways to tile a size n staircase polyomino with staircase polyominoes in the same direction as the size n staircase polyomino. %C A335547 A size-n staircase polynomo is a polyomino consisting of n left-aligned rows in increasing length of 1, 2, ..., n. %H A335547 Code Golf Stack Exchange user "Bubbler", <a href="https://codegolf.stackexchange.com/q/210748/53884">Tiling a staircase with staircases</a>. %H A335547 Rémy Sigrist, <a href="/A335547/a335547.gp.txt">PARI program for A335547</a> %e A335547 For n = 3 the a(3) = 5 tilings are: %e A335547 +---+ +---+ +---+ +---+ %e A335547 | | | | | | | | %e A335547 +---+---+ + +---+ +---+---+ +---+---+ %e A335547 | | | | | | | | | | | %e A335547 +---+---+---+, +---+---+---+, + +---+---+, +---+ +---+, %e A335547 | | | | | | | | | | | | | | %e A335547 +---+---+---+ +---+---+---+ +---+---+---+ +---+---+---+ %e A335547 +---+ %e A335547 | | %e A335547 + +---+ %e A335547 | | %e A335547 + +---+. %e A335547 | | %e A335547 +---+---+---+ %e A335547 For n = 4 the a(4) = 5+5+3+3+2 = 18 tilings are: %e A335547 +---+ +---+ +---+ %e A335547 | | | | | | %e A335547 +---+---+ +---+---+ +---+---+ %e A335547 | | | | | | | | | %e A335547 +---+---+---+ +---+---+---+ +---+---+---+ %e A335547 | | | | | | | | | | | | %e A335547 +---+---+---+---+, + +---+---+---+, +---+ +---+---+, %e A335547 | | | | | | | | | | | | | %e A335547 +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ %e A335547 +---+ +---+ +---+ %e A335547 | | | | | | %e A335547 +---+---+ +---+---+ + +---+ %e A335547 | | | | | | | | %e A335547 +---+---+---+ +---+---+---+ +---+---+---+ %e A335547 | | | | | | | | | | | | %e A335547 +---+---+ +---+, + +---+ +---+, +---+---+---+---+, %e A335547 | | | | | | | | | | | | %e A335547 +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ %e A335547 +---+ +---+ +---+ %e A335547 | | | | | | %e A335547 + +---+ + +---+ + +---+ %e A335547 | | | | | | %e A335547 +---+---+---+ +---+---+---+ +---+---+---+ %e A335547 | | | | | | | | | | | | %e A335547 + +---+---+---+, +---+ +---+---+, +---+---+ +---+, %e A335547 | | | | | | | | | | | | %e A335547 +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ %e A335547 +---+ +---+ +---+ %e A335547 | | | | | | %e A335547 + +---+ +---+---+ +---+---+ %e A335547 | | | | | | | | %e A335547 +---+---+---+ + +---+---+ + +---+---+ %e A335547 | | | | | | | | | | %e A335547 + +---+ +---+, +---+---+---+---+, + +---+---+, %e A335547 | | | | | | | | | | | %e A335547 +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ %e A335547 +---+ +---+ +---+ %e A335547 | | | | | | %e A335547 +---+---+ +---+---+ +---+---+ %e A335547 | | | | | | | | | %e A335547 + +---+---+ +---+ +---+ +---+ +---+ %e A335547 | | | | | | | | | %e A335547 +---+---+ +---+, +---+---+---+---+, + +---+---+---+, %e A335547 | | | | | | | | | | | | | %e A335547 +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ %e A335547 +---+ +---+ +---+ %e A335547 | | | | | | %e A335547 +---+---+ + +---+ + +---+ %e A335547 | | | | | | | %e A335547 +---+ +---+ + +---+ + +---+ %e A335547 | | | | | | | %e A335547 +---+ +---+, +---+---+---+---+, + +---+. %e A335547 | | | | | | | | | | %e A335547 +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ %e A335547 a(5) = 8+5+5+5+3+8+5+5+5+3+8+3+5+8+5+3+8+2 = 94. %o A335547 (PARI) See Links section. %Y A335547 Cf. A334617, A335967, A336479. %K A335547 nonn %O A335547 1,2 %A A335547 _Seiichi Manyama_, Sep 12 2020 %E A335547 More terms from _Rémy Sigrist_, Sep 13 2020