%I #20 Sep 22 2025 16:01:23
%S 1,1,1,1,-1,1,1,-1,0,1,1,-1,2,1,1,1,-1,2,-4,1,1,1,-1,2,-6,9,-2,1,1,-1,
%T 2,-6,22,-22,-9,1,1,-1,2,-6,24,-95,54,-9,1,1,-1,2,-6,24,-118,472,-139,
%U 50,1,1,-1,2,-6,24,-120,683,-2638,372,267,1,1,-1,2,-6,24
%N Square array read by ascending antidiagonals, complementary Bell numbers iterated by the Bell transform.
%H Peter Luschny, <a href="https://oeis.org/wiki/User:Peter_Luschny/BellTransform">The Bell transform</a>
%e [ 1, 1, 1, 1, 1, 1, 1, 1, 1, ...] A000012
%e [ 1, -1, 0, 1, 1, -2, -9, -9, 50, ...] A000587
%e [ 1, -1, 2, -4, 9, -22, 54, -139, 372, ...] A265023
%e [ 1, -1, 2, -6, 22, -95, 472, -2638, 16343, ...]
%e [ 1, -1, 2, -6, 24, -118, 683, -4533, 33862, ...]
%e [ 1, -1, 2, -6, 24, -120, 718, -4989, 39405, ...]
%e [... ...]
%e [ 1, -1, 2, -6, 24, -120, 720, -5040, 40320, ...] A133942
%o (SageMath) # uses[bell_transform from A264428]
%o def complementary_bell_number_matrix(ord, len):
%o b = [1]*len; L = [b]
%o for k in (1..ord-1):
%o b = [sum((-1)^n*c for (n, c) in enumerate(bell_transform(n, b))) for n in range(len)]
%o L.append(b)
%o return matrix(ZZ, L)
%o print(complementary_bell_number_matrix(6,9))
%Y Cf. A000012, A000587, A133942, A264428, A265023, A265312.
%K sign,tabl
%O 0,13
%A _Peter Luschny_, Dec 06 2015