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 A022170 #34 May 09 2025 08:43:26 %S A022170 1,1,1,1,7,1,1,43,43,1,1,259,1591,259,1,1,1555,57535,57535,1555,1,1, %T A022170 9331,2072815,12485095,2072815,9331,1,1,55987,74630671,2698853335, %U A022170 2698853335,74630671,55987,1,1,335923 %N A022170 Triangle of Gaussian binomial coefficients [ n,k ] for q = 6. %D A022170 F. J. MacWilliams and N. J. A. Sloane, The Theory of Error-Correcting Codes, Elsevier-North Holland, 1978, p. 698. %H A022170 G. C. Greubel, <a href="/A022170/b022170.txt">Rows n=0..50 of triangle, flattened</a> %H A022170 R. Mestrovic, <a href="http://arxiv.org/abs/1409.3820">Lucas' theorem: its generalizations, extensions and applications (1878--2014)</a>, arXiv preprint arXiv:1409.3820 [math.NT], 2014. %H A022170 Kent E. Morrison, <a href="http://www.cs.uwaterloo.ca/journals/JIS/VOL9/Morrison/morrison37.html">Integer Sequences and Matrices Over Finite Fields</a>, Journal of Integer Sequences, Vol. 9 (2006), Article 06.2.1. %H A022170 <a href="/index/Ga#Gaussian_binomial_coefficients">Index entries for sequences related to Gaussian binomial coefficients</a> %F A022170 T(n,k) = T(n-1,k-1) + q^k * T(n-1,k). - _Peter A. Lawrence_, Jul 13 2017 %F A022170 G.f. of column k: x^k * exp( Sum_{j>=1} f((k+1)*j)/f(j) * x^j/j ), where f(j) = 6^j - 1. - _Seiichi Manyama_, May 09 2025 %e A022170 Triangle begins: %e A022170 1; %e A022170 1, 1; %e A022170 1, 7, 1; %e A022170 1, 43, 43, 1; %e A022170 1, 259, 1591, 259, 1; %e A022170 1, 1555, 57535, 57535, 1555, 1; %e A022170 1, 9331, 2072815, 12485095, 2072815, 9331, 1; %e A022170 1, 55987, 74630671, 2698853335, 2698853335, 74630671, 55987, 1 ; %p A022170 A027873 := proc(n) %p A022170 mul(6^i-1,i=1..n) ; %p A022170 end procc: %p A022170 A022170 := proc(n,m) %p A022170 A027873(n)/A027873(m)/A027873(n-m) ; %p A022170 end proc: # _R. J. Mathar_, Jul 19 2017 %t A022170 p[n_]:= Product[6^i - 1, {i, 1, n}]; t[n_, k_]:= p[n]/(p[k]*p[n-k]); Table[t[n, k], {n, 0, 15}, {k, 0, n}]//Flatten (* _Vincenzo Librandi_, Aug 13 2016 *) %t A022170 Table[QBinomial[n,k,6], {n,0,10}, {k,0,n}]//Flatten (* or *) q:= 6; T[n_, 0]:= 1; T[n_,n_]:= 1; T[n_,k_]:= T[n,k] = If[k < 0 || n < k, 0, T[n-1, k -1] +q^k*T[n-1,k]]; Table[T[n,k], {n,0,10}, {k,0,n}] // Flatten (* _G. C. Greubel_, May 27 2018 *) %o A022170 (PARI) {q=6; T(n,k) = if(k==0,1, if (k==n, 1, if (k<0 || n<k, 0, T(n-1,k-1) + q^k*T(n-1,k))))}; %o A022170 for(n=0,10, for(k=0,n, print1(T(n,k), ", "))) \\ _G. C. Greubel_, May 27 2018 %Y A022170 Cf. A003463 (k=1), A022220 (k=2), A022221 (k=3). %K A022170 nonn,tabl %O A022170 0,5 %A A022170 _N. J. A. Sloane_