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 A117335 #4 Mar 30 2012 18:36:56 %S A117335 1,1,1,1,-1,1,1,6,-4,1,1,-27,24,-8,1,1,164,-157,66,-13,1,1,-1133,1176, %T A117335 -571,146,-19,1,1,8930,-9853,5335,-1621,281,-26,1,1,-78739,91498, %U A117335 -53989,18635,-3909,491,-34,1,1,768276,-933451,591157,-225490,54430,-8382,799,-43,1 %N A117335 Matrix inverse of triangle A117334. %e A117335 Triangle begins: %e A117335 1; %e A117335 1,1; %e A117335 1,-1,1; %e A117335 1,6,-4,1; %e A117335 1,-27,24,-8,1; %e A117335 1,164,-157,66,-13,1; %e A117335 1,-1133,1176,-571,146,-19,1; %e A117335 1,8930,-9853,5335,-1621,281,-26,1; %e A117335 1,-78739,91498,-53989,18635,-3909,491,-34,1; %e A117335 1,768276,-933451,591157,-225490,54430,-8382,799,-43,1; ... %e A117335 Matrix inverse yields A117334: %e A117335 1; %e A117335 -1,1; %e A117335 -2,1,1; %e A117335 -3,-2,4,1; %e A117335 -4,-13,8,8,1; %e A117335 -5,-44,-3,38,13,1; %e A117335 -6,-123,-117,125,101,19,1; %e A117335 -7,-314,-718,205,594,213,26,1; ... %e A117335 in which column k+1 is the Binomial transform of column k %e A117335 preceded by a zero (includes the k zeros above diagonal): %e A117335 column 1 = BINOMIAL[0, 1,-1,-2,-3,-4,-5,...] %e A117335 = [0,1,1,-2,-13,-44,-123,-314,-761,...]; %e A117335 column 2 = BINOMIAL[0, 0,1,1,-2,-13,-44,-123,-314,...] %e A117335 = [0,0,1,4,8,-3,-117,-718,-3314,...]. %Y A117335 Cf. A117334 (inverse), A117336 (column 1), A117337 (column 2), A117338 (row sums). %K A117335 sign,tabl %O A117335 0,8 %A A117335 _Paul D. Hanna_, Mar 09 2006