A059145 A hierarchical sequence (S(W3{2,2}*cc) - see A059126).

15, 54, 141, 324, 699, 1458, 2985, 6048, 12183, 24462, 49029, 98172, 196467, 393066, 786273, 1572696, 3145551, 6291270, 12582717, 25165620, 50331435, 100663074, 201326361, 402652944, 805306119, 1610612478, 3221225205, 6442450668, 12884901603, 25769803482

Offset

0,1

Links

Table of n, a(n) for n=0..29.

Jonas Wallgren, Hierarchical sequences

Index entries for linear recurrences with constant coefficients, signature (4, -5, 2).

Formula

Conjectures from Colin Barker, Oct 07 2015: (Start)

a(n) = 3*(-11 + 2^(4+n) - 3*n) = 3*A109363(n+2).

a(n) = 4*a(n-1) - 5*a(n-2) + 2*a(n-3) for n > 2.

G.f.: 3*(2*x-5) / ((x-1)^2*(2*x-1)).

(End)

Crossrefs

Cf. A059126.

Sequence in context: A063436 A010004 A172073 * A086643 A296324 A240814

Adjacent sequences: A059142 A059143 A059144 * A059146 A059147 A059148

Keyword

nonn

Author

Jonas Wallgren, Jan 19 2001

Extensions

More terms from Sean A. Irvine, Sep 13 2022

Status

approved