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 A174378 #6 Nov 29 2021 01:04:52 %S A174378 1,1,1,1,8,1,1,12,12,1,1,16,192,16,1,1,20,320,320,20,1,1,24,480,7680, %T A174378 480,24,1,1,28,672,13440,13440,672,28,1,1,32,896,21504,430080,21504, %U A174378 896,32,1,1,36,1152,32256,774144,774144,32256,1152,36,1,1,40,1440,46080,1290240,30965760,1290240,46080,1440,40,1 %N A174378 Triangle T(n, k) = n!*q^k/(n-k)! if floor(n/2) > k-1 otherwise n!*q^(n-k)/k!, with q = 4, read by rows. %C A174378 Row sums are: {1, 2, 10, 26, 226, 682, 8690, 28282, 474946, 1615178, ...}. %H A174378 G. C. Greubel, <a href="/A174378/b174378.txt">Rows n = 0..50 of the triangle, flattened</a> %F A174378 T(n, k) = n!*q^k/(n-k)! if floor(n/2) > k-1 otherwise n!*q^(n-k)/k!, with q = 2. %F A174378 T(n, n-k) = T(n, k). %F A174378 T(2*n, n) = A052734(n+1). - _G. C. Greubel_, Nov 28 2021 %e A174378 Triangle begins as: %e A174378 1; %e A174378 1, 1; %e A174378 1, 8, 1; %e A174378 1, 12, 12, 1; %e A174378 1, 16, 192, 16, 1; %e A174378 1, 20, 320, 320, 20, 1; %e A174378 1, 24, 480, 7680, 480, 24, 1; %e A174378 1, 28, 672, 13440, 13440, 672, 28, 1; %e A174378 1, 32, 896, 21504, 430080, 21504, 896, 32, 1; %e A174378 1, 36, 1152, 32256, 774144, 774144, 32256, 1152, 36, 1; %e A174378 1, 40, 1440, 46080, 1290240, 30965760, 1290240, 46080, 1440, 40, 1; %t A174378 T[n_, k_, q_]:= If[Floor[n/2]>=k, n!*q^k/(n-k)!, n!*q^(n-k)/k!]; %t A174378 Table[T[n, k, 4], {n,0,12}, {k,0,n}]//Flatten %o A174378 (Sage) %o A174378 f=factorial %o A174378 def T(n,k,q): return f(n)*q^k/f(n-k) if ((n//2)>k-1) else f(n)*q^(n-k)/f(k) %o A174378 flatten([[T(n,k,4) for k in (0..n)] for n in (0..12)]) # _G. C. Greubel_, Nov 28 2021 %Y A174378 Cf. A159623 (q=1), A174376 (q=2), A174377 (q=3), this sequence (q=4). %Y A174378 Cf. A052734. %K A174378 nonn,tabl,easy %O A174378 0,5 %A A174378 _Roger L. Bagula_, Mar 17 2010 %E A174378 Edited by _G. C. Greubel_, Nov 28 2021