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A245477
Period 6: repeat [1, 1, 1, 1, 1, 2].
2
1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1
OFFSET
0,6
COMMENTS
First differences of A047368. The first differences of this sequence are in A131533. - Wesley Ivan Hurt, Jul 24 2014
Binomial Transform of a(n) gives: 1, 2, 4, 8, 16, 33, 70, 149, 312, 638, 1276, 2511, ... - Wesley Ivan Hurt, Aug 13 2014
FORMULA
a(n) = floor((n+1)*7/6) - floor((n)*7/6).
G.f.: 1/(1-x) + x^5/(1-x^6). - Robert Israel, Jul 23 2014
From Wesley Ivan Hurt, Jul 24 2014, Aug 06-29 2014: (Start)
a(n) = 2 - sign((n+1) mod 6).
a(n) = 3 - 2^sign((n+1) mod 6).
a(n) = A172051(n) + 1.
a(2n) = 1, a(2n+1) = A177702(n).
Sum_{i=0..n-2} a(i) = A047368(n), n>0.
a(n) = 1 + mod(n, 1 + mod(n-1, 3)).
a(n) = 1 + binomial(mod(5n + 10, 6), 5). (End)
From Wesley Ivan Hurt, Jun 23 2016: (Start)
a(n) = a(n-6) for n>5.
a(n) = (7 - cos(n*Pi) + cos(n*Pi/3) - cos(2*n*Pi/3) - sqrt(3)*sin(n*Pi/3) - sqrt(3)*sin(2*n*Pi/3))/6. (End)
MAPLE
A:= n -> piecewise(n mod 6 = 5, 2, 1);
seq(A(n), n=0..100); # Robert Israel, Jul 23 2014
MATHEMATICA
Table[2 - Sign[Mod[n + 1, 6]], {n, 0, 100}] (* Wesley Ivan Hurt, Jul 24 2014 *)
PadRight[{}, 120, {1, 1, 1, 1, 1, 2}] (* Harvey P. Dale, Jun 02 2016 *)
PROG
(Sage)
[floor((n+1)*7/6) - floor((n)*7/6) for n in [0..200]]
(PARI) a(n) = 7*(n+1)\6 - 7*n\6; \\ Michel Marcus, Jul 23 2014
(Magma) [Floor((n+1)*7/6) - Floor((n)*7/6) : n in [0..100]]; // Wesley Ivan Hurt, Aug 06 2014
KEYWORD
nonn,easy
AUTHOR
Hailey R. Olafson, Jul 23 2014
STATUS
approved