A038073 - OEIS

%I #22 Jun 19 2018 15:52:15

%S -1,-1,0,0,1,0,-1,-1,1,2,0,-3,-3,2,8,4,-10,-18,1,36,33,-36,-102,-33,

%T 170,238,-95,-578,-401,762,1599,97,-3184,-3493,2950,10277,4570,-16611,

%U -26794,6751,63040,51658,-78369,-190465,-34209,365790,455401,-296331,-1275020

%N Shifts left under Weigh transform.

%H Alois P. Heinz, <a href="/A038073/b038073.txt">Table of n, a(n) for n = 1..1000</a>

%H N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>

%p b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,

%p       add(binomial(a(i), j)*b(n-i*j, i-1), j=0..n/i)))

%p     end:

%p a:= n-> `if`(n<2, -1, b((n-1)$2)):

%p seq(a(n), n=1..60); # _Alois P. Heinz_, May 20 2013

%t b[n_, i_] := b[n, i] = If[n==0, 1, If[i<1, 0, Sum[Binomial[a[i], j]*b[n-i*j, i-1], {j, 0, n/i}]]]; a[n_] := If[n<2, -1, b[n-1, n-1]]; Table[a[n], {n, 1, 60}] (* _Jean-François Alcover_, Feb 27 2017, after _Alois P. Heinz_ *)

%Y Cf. A038072, A038074.

%K sign,eigen

%O 1,10

%A _Christian G. Bower_, Jan 04 1999