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 A180058 #20 Jul 22 2020 11:39:24 %S A180058 2,6,120,3003 %N A180058 Smallest number occurring in exactly n rows of Pascal's triangle. %C A180058 A059233(a(n)) = n and A059233(m) < n for m < a(n). %H A180058 Wikipedia, <a href="http://en.wikipedia.org/wiki/Singmaster's_conjecture">Singmaster's conjecture</a> %H A180058 <a href="/index/Pas#Pascal">Index entries for triangles and arrays related to Pascal's triangle</a> %e A180058 . n A180058 referred equal binomial coefficients (A007318) A059233 %e A180058 . - ------- ---------------------------------------------- ------- %e A180058 . 1 2 C (2, 1) 1 %e A180058 . 2 6 C (4, 2) C (6, 1) 2 %e A180058 . 3 120 C (10, 3) C (16, 2) C (120, 1) 3 %e A180058 . 4 3003 C (14, 6) C (15, 5) C (78, 2) C (3003, 1) 4 . %o A180058 (Haskell) %o A180058 import Data.List (elemIndex) %o A180058 import Data.Maybe (fromJust) %o A180058 a180058 = (+ 2) . fromJust . (`elemIndex` a059233_list) %Y A180058 Cf. A185024, A182237, A098565, A003015, A003016. %K A180058 nonn,more %O A180058 1,1 %A A180058 _Reinhard Zumkeller_, Dec 24 2012