The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A294364 Linear recurrence with signature (1,1,-1,1,1), where the first terms are powers of 2 (1,2,4,8,16). 0
 1, 2, 4, 8, 16, 23, 37, 56, 94, 152, 250, 401, 649, 1046, 1696, 2744, 4444, 7187, 11629, 18812, 30442, 49256, 79702, 128957, 208657, 337610, 546268, 883880, 1430152, 2314031, 3744181, 6058208, 9802390, 15860600, 25662994, 41523593, 67186585, 108710174, 175896760, 284606936 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS The interest of this sequence mainly lies in the peculiarities of its array of successive differences, which begins: 1,    2,   4,   8,  16,  23,  37,  56,  94, ... 1,    2,   4,   8,   7,  14,  19,  38,  58, ... 1,    2,   4,  -1,   7,   5,  19,  20,  40, ... 1,    2,  -5,   8,  -2,  14,   1,  20,  13, ... 1,   -7,  13, -10,  16, -13,  19,  -7,  31, ... -8,  20, -23,  26, -29,  32, -26,  38, -23, ... 28, -43,  49, -55,  61, -58,  64, -61,  67, ... The main diagonal is A000079 (powers of 2). The first upper subdiagonal is A254076. The second upper subdiagonal (4, 8, 7, 14, 19, 38, ...) is not in the OEIS. The third upper subdiagonal is A185346 (2^n-9). Every row, once computed mod 9, is 6-periodic, repeating (1, 2, 4, 8, 7, 5) (A153130). LINKS Index entries for linear recurrences with constant coefficients, signature (1,1,-1,1,1). FORMULA G.f.: (1+x+x^2+3*x^3+5*x^4) / (1-x-x^2+x^3-x^4-x^5). a(n) = (9/2)*fibonacci(n) + (-1)^n - sqrt(3)*sin(n*Pi/3). a(n) ~ (9/2)*fibonacci(n). MATHEMATICA LinearRecurrence[{1, 1, -1, 1, 1}, {1, 2, 4, 8, 16}, 40] CROSSREFS Cf. A000045, A000079, A153130, A185346, A254076. Sequence in context: A062729 A004620 A018618 * A108566 A057615 A018416 Adjacent sequences:  A294361 A294362 A294363 * A294365 A294366 A294367 KEYWORD nonn,easy AUTHOR Jean-François Alcover and Paul Curtz, Oct 29 2017 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified July 25 13:05 EDT 2021. Contains 346290 sequences. (Running on oeis4.)