A159747 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 10. See A159741 for details.

89, 504, 1490, 3525, 7617, 15808, 32192, 64960, 130496, 261568, 523712, 1048000, 2096576, 4193728, 8388032, 16776640, 33553856, 67108288, 134217152, 268434880, 536870336, 1073741248, 2147483072, 4294966720, 8589934016, 17179868608, 34359737792, 68719476160, 137438952896

Offset

1,1

Links

Table of n, a(n) for n=1..29.

Formula

Interpolate a(n)=(-2*n^4+22*n^3-107.5*n^2+276.5*n+1245)/3 offset 0 & b(n)=(2*n^4-18*n^3+77.5*n^2-184.5*n+1713)/3 offset 0. Add a leading 89. Binomially transform. [From Al Hakanson (hawkuu(AT)gmail.com), Jun 08 2009]

a(n) = T(n+9,n+1) with T defined in A159741. a(n) = 2^(n+8)-576 for n>=6. - R. J. Mathar, Feb 04 2021

Crossrefs

Sequence in context: A279366 A142904 A172523 * A141866 A176634 A224740

Adjacent sequences: A159744 A159745 A159746 * A159748 A159749 A159750

Keyword

nonn,easy

Author

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

Extensions

a(8) and beyond by R. J. Mathar, Feb 04 2021

Status

approved