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 A260693 #26 Apr 07 2020 15:56:39 %S A260693 1,0,1,0,1,2,0,1,6,9,0,1,14,46,64,0,1,30,175,465,625,0,1,62,596,2471, %T A260693 5901,7776,0,1,126,1925,11634,40376,90433,117649,0,1,254,6042,51570, %U A260693 243454,757940,1626556,2097152,0,1,510,18651,220887,1376715,5580021,16146957,33609537,43046721 %N A260693 Triangle read by rows: T(n,k) is the number of parking functions of length n whose maximum element is k, where n >= 0 and 0 <= k <= n. %C A260693 Elements in each row are increasing. %H A260693 Alois P. Heinz, <a href="/A260693/b260693.txt">Rows n = 0..140, flattened</a> %F A260693 T(n,0) = A000007(n). %F A260693 T(n,1) = 1 for n>0. %F A260693 T(n,2) = 2^n - 2 = A000918(n). %F A260693 T(n,n) = n^(n-1) = A000169(n) for n>0. %F A260693 Sum of n-th row is A000272(n+1). %F A260693 T(2n,n) = A291121(n). - _Alois P. Heinz_, Aug 17 2017 %e A260693 For example, T(3,2) = 6 because there are six parking functions of length 3 whose maximum element is 2, namely (1,1,2), (1,2,1), (2,1,1), (1,2,2), (2,1,2), (2,2,1). %e A260693 Triangle starts: %e A260693 1; %e A260693 0, 1; %e A260693 0, 1, 2; %e A260693 0, 1, 6, 9; %e A260693 0, 1, 14, 46, 64; %e A260693 0, 1, 30, 175, 465, 625; %e A260693 0, 1, 62, 596, 2471, 5901, 7776; %e A260693 0, 1, 126, 1925, 11634, 40376, 90433, 117649; %e A260693 0, 1, 254, 6042, 51570, 243454, 757940, 1626556, 2097152; %e A260693 0, 1, 510, 18651, 220887, 1376715, 5580021, 16146957, 33609537, 43046721; %e A260693 ... %Y A260693 Cf. A000007, A000169, A000272, A000918, A291121. %K A260693 nonn,tabl %O A260693 0,6 %A A260693 _Ran Pan_, Nov 16 2015 %E A260693 Edited by _Alois P. Heinz_, Nov 26 2015