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A107906
Expansion of (1+8x)/(1-16x^2).
2
1, 8, 16, 128, 256, 2048, 4096, 32768, 65536, 524288, 1048576, 8388608, 16777216, 134217728, 268435456, 2147483648, 4294967296, 34359738368, 68719476736, 549755813888, 1099511627776, 8796093022208, 17592186044416
OFFSET
0,2
COMMENTS
Fifth binomial transform is A096053.
FORMULA
a(n) = ((1+sqrt(4))*(2*sqrt(4))^n + (1-sqrt(4))*(-2*sqrt(4))^n)/2;
a(n) = 3*4^n/2 - (-4)^n/2.
a(2n) = 16^n, a(2n+1) = 8*16^n.
CROSSREFS
Sequence in context: A264478 A277364 A278312 * A328127 A323385 A061359
KEYWORD
easy,nonn
AUTHOR
Paul Barry, May 27 2005
STATUS
approved