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A354546
Expansion of e.g.f. exp(x)^( cos(x) - sin(x) ).
1
1, 1, -1, -8, -7, 96, 385, -1210, -14943, -5912, 593361, 2409298, -22935647, -236575468, 590041257, 20313729886, 40488350401, -1659176093392, -11796304552991, 120680593857514, 1966312603184321, -4949789957167124, -288454178376442407, -849587090710029098
OFFSET
0,4
FORMULA
a(0) = 1; a(n) = Sum_{k=1..n} (-1)^floor(k/2) * k * binomial(n-1,k-1) * a(n-k).
PROG
(PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(exp(x)^(cos(x)-sin(x))))
(PARI) a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=sum(j=1, i, (-1)^(j\2)*j*binomial(i-1, j-1)*v[i-j+1])); v;
CROSSREFS
KEYWORD
sign
AUTHOR
Seiichi Manyama, Aug 18 2022
STATUS
approved