A159748 If an array is made of columns of -nacci sequences, fibo-, tribo- etc. all starting w. 1,1,2 etc, the NW to SE diagonals can be extended by computation. The above is diagonal 11. See A159741 for details.

144, 927, 2872, 6930, 15109, 31489, 64256, 129792, 260864, 523008, 1047296, 2095872, 4193024, 8387328, 16775936, 33553152, 67107584, 134216448, 268434176, 536869632, 1073740544, 2147482368, 4294966016, 8589933312, 17179867904

Offset

1,1

Links

Table of n, a(n) for n=1..25.

Formula

a(n) = 3*a(n-1) - 2*a(n-2), n > 8. - R. J. Mathar, Apr 22 2009

Interpolate a(n) = (4*n^5 - 60*n^4 + 415*n^3 - 1665*n^2 + 3826*n + 11745)/15 offset 0 and b(n) = -4*n^5 + 50*n^4 - 305*n^3 + 1127.5*n^2 - 2443.5 + 17430)/15 offset 0. Add the leading 144. Binomially transform. - Al Hakanson (hawkuu(AT)gmail.com), Jun 08 2009

Maple

T := proc(n, m) option remember ; if n < 0 then 0; elif n <= 1 then 1; elif n = 2 then 2; else add(procname(n-i, m), i=1..m) ; fi: end: A159748 := proc(n) T(n+10, n+1) ; end: seq(A159748(n), n=1..40) ; # R. J. Mathar, Apr 22 2009

Crossrefs

Cf. A159741 .

Sequence in context: A223235 A187301 A120089 * A235957 A162669 A230796

Adjacent sequences: A159745 A159746 A159747 * A159749 A159750 A159751

Keyword

nonn

Author

Al Hakanson (hawkuu(AT)gmail.com), Apr 20 2009

Extensions

More terms from R. J. Mathar, Apr 22 2009

Status

approved