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A256871
a(n) = 2^(n-1)*(2^n+11).
3
6, 13, 30, 76, 216, 688, 2400, 8896, 34176, 133888, 529920, 2108416, 8411136, 33599488, 134307840, 537051136, 2147844096, 8590655488, 34361180160, 137441837056, 549761581056, 2199034789888, 8796116090880, 35184418226176, 140737580630016, 562950137970688
OFFSET
0,1
COMMENTS
a(A102633(n)) is a subsequence of A141549.
FORMULA
G.f.: (6-23*x)/((1-4*x)*(1-2*x)). - Vincenzo Librandi, Apr 24 2015
a(n) = 6*a(n-1)-8*a(n-2). - Colin Barker, Apr 26 2015
MATHEMATICA
Table[2^(n - 1) (2^n + 11), {n, 0, 30}] (* Vincenzo Librandi, Apr 24 2015 *)
LinearRecurrence[{6, -8}, {6, 13}, 40] (* Harvey P. Dale, Jan 29 2022 *)
PROG
(PARI) A256871(n)=2^(n-1)*(2^n+11)
(Magma) [2^(n-1)*(2^n+11): n in [0..30]]; // Vincenzo Librandi, Apr 24 2015
(PARI) Vec((6-23*x)/((1-4*x)*(1-2*x)) + O(x^100)) \\ Colin Barker, Apr 26 2015
CROSSREFS
Sequence in context: A159694 A145976 A101622 * A192304 A343544 A147330
KEYWORD
nonn,easy
AUTHOR
M. F. Hasler, Apr 24 2015
STATUS
approved