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A133572
Row sums of triangle A133571.
2
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
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
KEYWORD
nonn,easy
AUTHOR
Gary W. Adamson, Sep 16 2007
STATUS
approved