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A154890 Jacobsthal numbers A001045 alternatingly incremented by 3 and 5. 2
3, 6, 4, 8, 8, 16, 24, 48, 88, 176, 344, 688, 1368, 2736, 5464, 10928, 21848, 43696, 87384, 174768, 349528, 699056, 1398104, 2796208, 5592408, 11184816, 22369624, 44739248, 89478488, 178956976, 357913944, 715827888, 1431655768, 2863311536, 5726623064 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..34.

FORMULA

a(2n+1) = 2*a(2n).

a(n) = A153643(n)+A010684(n).

a(n+2) = 4*A128209(n).

a(n) = 2*a(n-1)+a(n-2)-2*a(n-3). G.f.: (3-11x^2)/((1-x)(1+x)(1-2x)). [R. J. Mathar, Jan 23 2009]

CROSSREFS

Sequence in context: A136612 A004546 A197255 * A248176 A100000 A083682

Adjacent sequences:  A154887 A154888 A154889 * A154891 A154892 A154893

KEYWORD

nonn,easy

AUTHOR

Paul Curtz, Jan 17 2009

EXTENSIONS

Edited and extended by R. J. Mathar, Jan 23 2009

STATUS

approved

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Last modified August 24 02:32 EDT 2017. Contains 291052 sequences.