a(n) = 5*a(n-1) - 5*a(n-2) + a(n-3) with a(1) = 1 and a(k) = 0 if k <= 0.

A061278

a(n) = 5*a(n-1) - 5*a(n-2) + a(n-3) with a(1) = 1 and a(k) = 0 if k <= 0.

Terms

    a(0) =0a(1) =1a(2) =5a(3) =20a(4) =76a(5) =285a(6) =1065a(7) =3976a(8) =14840a(9) =55385a(10) =206701a(11) =771420a(12) =2878980a(13) =10744501a(14) =40099025a(15) =149651600a(16) =558507376a(17) =2084377905a(18) =7779004245a(19) =29031639076a(20) =108347552060a(21) =404358569165

External references