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A196410
a(n) = n*2^(n-5).
1
5, 12, 28, 64, 144, 320, 704, 1536, 3328, 7168, 15360, 32768, 69632, 147456, 311296, 655360, 1376256, 2883584, 6029312, 12582912, 26214400, 54525952, 113246208, 234881024, 486539264, 1006632960, 2080374784, 4294967296, 8858370048, 18253611008, 37580963840, 77309411328, 158913789952
OFFSET
5,1
FORMULA
G.f.: x^5*( 5-8*x ) / (2*x-1)^2 . - R. J. Mathar, Oct 13 2011
From Amiram Eldar, Jan 12 2021: (Start)
Sum_{n>=5} 1/a(n) = 32*log(2) - 131/6.
Sum_{n>=5} (-1)^(n+1)/a(n) = 32*log(3/2) - 77/6. (End)
MATHEMATICA
Table[n*2^(n-5), {n, 5, 37}] (* Amiram Eldar, Jan 12 2021 *)
PROG
(Magma) [n*2^(n-5): n in [5..40]]
CROSSREFS
Sequence in context: A038376 A002767 A055245 * A000465 A283506 A266471
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Oct 04 2011
STATUS
approved