A297629 a(n) = A297628(n,1).

0, 1, 2, 5, 20, 137, 1478, 22925, 481448, 13138193, 451749962, 19104365333, 974417603132, 58981977530777, 4179837144348686, 342799255549127837, 32212592211380729168, 3438255899105307857441, 413670348773363088131474, 55722273751954119897519653, 8352810415786907670280952420

Offset

0,3

Links

Table of n, a(n) for n=0..20.

Prog

(Julia)
function A297629List(len::Int)
    R = Array{BigInt}(len)
    A = fill(BigInt(0), len+1); A[1] = 1
    for n in 1:len
        for k in n:-1:2 A[k] += A[k+1] end
        for k in 2: 1:n A[k] += A[k-1] end
        R[n] = A[2]
    end
    return R
end
println(A297629List(20))

Crossrefs

Cf. A297628.

Sequence in context: A006366 A012317 A297630 * A118181 A140988 A136650

Adjacent sequences: A297626 A297627 A297628 * A297630 A297631 A297632

Keyword

nonn

Author

Peter Luschny, Jan 02 2018

Status

approved