W. Lang, Jul 13 2007 a(n,m) tabl head (triangle) for A130757 n\m 0 1 2 3 4 5 6 7 8 ... 0 1 0 0 0 0 0 0 0 0 1 3 -1 0 0 0 0 0 0 0 2 15 -10 1 0 0 0 0 0 0 3 105 -105 21 -1 0 0 0 0 0 4 945 -1260 378 -36 1 0 0 0 0 5 10395 -17325 6930 -990 55 -1 0 0 0 6 135135 -270270 135135 -25740 2145 -78 1 0 0 7 2027025 -4729725 2837835 -675675 75075 -4095 105 -1 0 8 34459425 -91891800 64324260 -18378360 2552550 -185640 7140 -136 1 . . . The next rows are: n=9: [654729075,-1964187225,1571349780,-523783260,87297210,-7936110,406980,-11628,171,-1] n=10: [13749310575, -45831035250, 41247931725, -15713497800, 3055402350, -333316620, 21366450, -813960, 17955, -210, 1]] ###################### Row sums (signed) give A131441: [1, 2, 6, 20, 28, -936, -23672, -469456, -9112560, -182135008, -3804634784,...]. Row sums (unsigned) give A066224: [1, 4, 26, 232, 2620, 35696, 568504, 10349536, 211799312, 4809701440, 119952692896,...]. ##################### Column sequences are, for m=0..3: A001147(n+1)=(2*n+1)!!, A000457, A001881, A130563. ######################################## e.o.f. ###############################################