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A251713
7-step Fibonacci sequence starting with (0,0,1,0,0,0,0).
4
0, 0, 1, 0, 0, 0, 0, 1, 2, 4, 7, 14, 28, 56, 112, 223, 444, 884, 1761, 3508, 6988, 13920, 27728, 55233, 110022, 219160, 436559, 869610, 1732232, 3450544, 6873360, 13691487, 27272952, 54326744, 108216929, 215564248, 429396264, 855341984, 1703810608, 3393929729
OFFSET
0,9
FORMULA
a(n+7) = a(n) + a(n+1) + a(n+2) + a(n+3) + a(n+4) + a(n+5) + a(n+6).
MATHEMATICA
LinearRecurrence[Table[1, {7}], {0, 0, 1, 0, 0, 0, 0}, 40] (* Michael De Vlieger, Dec 09 2014 *)
PROG
(J) (see www.jsoftware.com) First construct the generating matrix
[M=: (#.@}: + {:)\"1&.|: <:/~i.7
1 1 1 1 1 1 1
1 2 2 2 2 2 2
2 3 4 4 4 4 4
4 6 7 8 8 8 8
8 12 14 15 16 16 16
16 24 28 30 31 32 32
32 48 56 60 62 63 64
Given that matrix, one can produce the first 7*150 numbers by
, M(+/ . *)^:(i.150) 0 0 1 0 0 0 0x
CROSSREFS
Other 7-step Fibonacci sequences are A066178, A104621, A122189, A251710, A251711, A251712, A251714.
Sequence in context: A057744 A251708 A293325 * A251744 A251751 A251765
KEYWORD
nonn,easy
AUTHOR
Arie Bos, Dec 07 2014
STATUS
approved