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%I #11 Jan 06 2019 03:58:30
%S 1,1,2,1,4,3,1,6,8,4,1,8,15,12,5,1,10,24,24,16,6,1,12,35,40,33,20,7,1,
%T 14,48,60,56,42,24,8,1,16,63,84,85,72,51,28,9,1,18,80,112,120,110,88,
%U 60,32,10
%N Array T(n,k) read by antidiagonals: coefficient [x^k] of (1 + n*Sum_{i>=1} x^i)^2, k >= 0.
%C Antidiagonal sums are in A136396.
%F T(n,0) = 1; T(n,k) = n*(2+n*(k-1)), k > 0. - _R. J. Mathar_, Jan 05 2011
%e First few rows of the array:
%e 1 2 3 4 5 6 7 8 9 10 11 A000027
%e 1 4 8 12 16 20 24 28 32 36 40 A008574
%e 1 6 15 24 33 42 51 60 69 78 87 A122709
%e 1 8 24 40 56 72 88 104 120 136 152 A051062
%e 1 10 35 60 85 110 135 160 185 210 235
%e 1 12 48 84 120 156 192 228 264 300 336
%e 1 14 63 112 161 210 259 308 357 406 455
%e 1 16 80 144 208 272 336 400 464 528 592
%e 1 18 99 180 261 342 423 504 585 666 747
%e Row n=3 is generated by (1 + 3x + 3x^2 + 3x^3 + 3x^4 + ...)^2 = 1 + 6x + 15x^2 + 24x^3 + ..., for example.
%p A179000 := proc(n,k) if k = 0 then 1; else 2*n+n^2*(k-1) ; end if; end proc: # _R. J. Mathar_, Jan 05 2011
%Y Cf. A136396, A179901.
%K nonn,tabl,easy
%O 1,3
%A _Gary W. Adamson_, Jan 03 2011
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