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A257272
a(n) = 2^(n-1)*(2^n+7).
4
4, 9, 22, 60, 184, 624, 2272, 8640, 33664, 132864, 527872, 2104320, 8402944, 33583104, 134275072, 536985600, 2147713024, 8590393344, 34360655872, 137440788480, 549759483904, 2199030595584, 8796107702272, 35184401448960, 140737547075584, 562950070861824, 2251800048566272, 9007199724503040
OFFSET
0,1
COMMENTS
For n in A057195, a(n) is of deficiency 8, i.e., in A125247.
Also, the third column (k=2) of the table given in A181444.
FORMULA
a(n) = 2^(n-1)*A168415(n).
n in A057195 <=> A168415(n) in A104066 <=> a(n) in A125247.
G.f.: (4-15*x)/((1-4*x)*(1-2*x)). - Vincenzo Librandi, Apr 27 2015
MATHEMATICA
Table[2^(n - 1) (2^n + 7), {n, 0, 30}] (* Bruno Berselli, Apr 27 2015 *)
CoefficientList[Series[(4 - 15 x)/((1 - 4 x) (1 - 2 x)), {x, 0, 30}], x] (* Vincenzo Librandi, Apr 27 2015 *)
PROG
(PARI) a(n)=2^(n-1)*(2^n+7)
(Magma) [2^(n-1)*(2^n+7): n in [0..25]]; // Vincenzo Librandi, Apr 27 2015
(PARI) Vec((4-15*x)/((1-4*x)*(1-2*x)) + O(x^100)) \\ Colin Barker, Apr 27 2015
KEYWORD
nonn,easy
AUTHOR
M. F. Hasler, Apr 27 2015
STATUS
approved