OFFSET
4,2
FORMULA
a(n)=A090438(n, 7)/48, n>=4.
a(n)=binomial(2*n-2, 5)*(2*n)!/(7!*4!*2)= A053132(n+1)*(2*n)!/(7!*4!), n>=4.
E.g.f.:(sum(((-1)^(p+1))*binomial(7, p)*hypergeom([(p-1)/2, p/2], [], 4*x), p=2..7) + 6)/(7!*48) (cf. A090438).
D-finite with recurrence (2*n-7)*(n-4)*a(n) -2*n*(n-1)*(2*n-1)*(2*n-3)*a(n-1)=0. - R. J. Mathar, Jul 27 2022
MAPLE
A091036 := proc(n)
binomial(2*n-2, 5)*(2*n)!/7!/4!/2 ;
end proc:
seq(A091036(n), n=4..40) ; # R. J. Mathar, Jul 27 2022
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wolfdieter Lang, Jan 23 2004
STATUS
approved