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 A176483 #13 May 07 2019 17:38:24 %S A176483 1,1,1,1,4,1,1,16,16,1,1,67,79,67,1,1,281,344,344,281,1,1,1176,1453, %T A176483 1504,1453,1176,1,1,4921,6093,6358,6358,6093,4921,1,1,20594,25511, %U A176483 26671,26885,26671,25511,20594,1,1,86185,106775,111680,112789,112789,111680,106775,86185,1 %N A176483 Triangle, read by rows, defined by T(n, k) = b(n) - b(k) - b(n-k) + 1, where b(n) = 5*b(n-1) - 4*b(n-2) + 3*b(n-3) - 2*b(n-4) - b(n-5) and b(0) = 0, b(1) = 1, b(2) = 5, b(3) = 21, b(4) = 88. %C A176483 Row sums are {1, 2, 6, 34, 215, 1252, 6764, 34746, 172439, 834860, 3967727, ...}. %H A176483 Indranil Ghosh, <a href="/A176483/b176483.txt">Rows 0..120, flattened</a> %H A176483 Indranil Ghosh, <a href="/A176483/a176483.txt">Python Program to generate the b-file</a> %F A176483 Let b(n) = 5*b(n-1) - 4*b(n-2) + 3*b(n-3) - 2*b(n-4) - b(n-5), with b(0) = 0, b(1) = 1, b(2) = 5, b(3) = 21, b(4) = 88, then T(n, k) = b(n) - b(k) - b(n-k) + 1. %e A176483 Triangle begins as: %e A176483 1; %e A176483 1, 1; %e A176483 1, 4, 1; %e A176483 1, 16, 16, 1; %e A176483 1, 67, 79, 67, 1; %e A176483 1, 281, 344, 344, 281, 1; %e A176483 1, 1176, 1453, 1504, 1453, 1176, 1; %e A176483 1, 4921, 6093, 6358, 6358, 6093, 4921, 1; %e A176483 1, 20594, 25511, 26671, 26885, 26671, 25511, 20594, 1; %e A176483 1, 86185, 106775, 111680, 112789, 112789, 111680, 106775, 86185, 1; %e A176483 ... %e A176483 T(3,2) = b(3) - b(2) - b(3 - 2) + 1 = 21 - 5 - 1 + 1 = 16 [b(1) = 1, b(2) = 5, b(3) = 21]. - _Indranil Ghosh_, Feb 17 2017 %t A176483 b[0]:=0; b[1]:=1; b[2]:=5; b[3]:=21; b[4]:=88; %t A176483 b[n_]:= 5*b[n-1] -4*b[n-2] +3*b[n-3] -2*b[n-4] -b[n-5]; %t A176483 T[n_, m_]:= b[n] -b[m] -b[n-m] +1; %t A176483 Table[T[n, m], {n,0,10}, {m,0,n}]//Flatten (* modified by _G. C. Greubel_, May 06 2019 *) %o A176483 (PARI) %o A176483 {b(n) = if(n==0, 0, if(n==1, 1, if(n==2, 5, if(n==3, 21, if(n==4, 88, 5*b(n-1) -4*b(n-2) +3*b(n-3) -2*b(n-4) -b(n-5))))))}; %o A176483 {T(n, k) = b(n) -b(k) -b(n-k) +1}; %o A176483 for(n=0,10, for(k=0,n, print1(T(n,k), ", "))) \\ _G. C. Greubel_, May 06 2019 %o A176483 (Sage) %o A176483 def b(n): %o A176483 if (n==0): return 0 %o A176483 elif (n==1): return 1 %o A176483 elif (n==2): return 5 %o A176483 elif (n==3): return 21 %o A176483 elif (n==4): return 88 %o A176483 else: return 5*b(n-1) -4*b(n-2) +3*b(n-3) -2*b(n-4) -b(n-5) %o A176483 def T(n, k): return b(n) - b(k) - b(n-k) + 1 %o A176483 [[T(n, k) for k in (0..n)] for n in (0..12)] # _G. C. Greubel_, May 06 2019 %Y A176483 Cf. A095263. %K A176483 nonn,tabl %O A176483 0,5 %A A176483 _Roger L. Bagula_, Apr 18 2010 %E A176483 Edited by _G. C. Greubel_, May 06 2019