A133572 Row sums of triangle A133571.

1, 4, 6, 16, 24, 64, 96, 256, 384, 1024, 1536, 4096, 6144, 16384, 24576, 65536, 98304, 262144, 393216, 1048576, 1572864, 4194304, 6291456, 16777216, 25165824, 67108864, 100663296, 268435456, 402653184, 1073741824, 1610612736, 4294967296

Offset

1,2

Links

Table of n, a(n) for n=1..32.

Index entries for linear recurrences with constant coefficients, signature (0, 4).

Formula

Even-indexed terms, a(n) = 2^n; odd-indexed terms, a(n) = 2^(n-1) + 2^(n-2).

G.f.: -x*(4*x+1+2*x^2)/(2*x-1)/(2*x+1). - R. J. Mathar, Nov 14 2007

Example

a(4) = 16 = sum or row 4 terms of triangle A133571: (5 + 5 + 5 + 1).
a(4) = 16 = 2^4.
a(7) = 96 = 2^6 + 2^5 = 64 + 32.

Crossrefs

Cf. A133571.

Sequence in context: A323043 A120375 A025618 * A121852 A321411 A242251

Adjacent sequences: A133569 A133570 A133571 * A133573 A133574 A133575

Keyword

nonn,easy

Author

Gary W. Adamson, Sep 16 2007

Status

approved