

A047526


Numbers that are congruent to {1, 2, 7} mod 8.


1



1, 2, 7, 9, 10, 15, 17, 18, 23, 25, 26, 31, 33, 34, 39, 41, 42, 47, 49, 50, 55, 57, 58, 63, 65, 66, 71, 73, 74, 79, 81, 82, 87, 89, 90, 95, 97, 98, 103, 105, 106, 111, 113, 114, 119, 121, 122, 127, 129, 130, 135, 137, 138, 143, 145, 146, 151, 153, 154, 159
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OFFSET

1,2


COMMENTS

Numbers h such that Fibonacci(h) mod 3 = 1.  Bruno Berselli, Oct 18 2017


LINKS

G. C. Greubel, Table of n, a(n) for n = 1..1000
Index entries for linear recurrences with constant coefficients, signature (1,0,1,1).


FORMULA

From Chai Wah Wu, May 30 2016: (Start)
a(n) = a(n1) + a(n3)  a(n4), for n > 4.
G.f.: x*(x^3 + 5*x^2 + x + 1)/(x^4  x^3  x + 1). (End)
From Wesley Ivan Hurt, Jun 10 2016: (Start)
a(n) = 8*n/3  2 + cos(2*n*Pi/3) + 5*sin(2*n*Pi/3)/(3*sqrt(3)).
a(3*k) = 8*k1, a(3*k1) = 8*k6, a(3*k2) = 8*k7. (End)


MAPLE

A047526:=n>8*n/32+cos(2*n*Pi/3)+5*sin(2*n*Pi/3)/(3*sqrt(3)): seq(A047526(n), n=1..100); # Wesley Ivan Hurt, Jun 10 2016


MATHEMATICA

LinearRecurrence[{1, 0, 1, 1}, {1, 2, 7, 9}, 50] (* G. C. Greubel, May 30 2016 *)


PROG

(MAGMA) [n: n in [0..150]  n mod 8 in [1, 2, 7]]; // Wesley Ivan Hurt, Jun 10 2016


CROSSREFS

Cf. A000045.
Cf. A008586: numbers h such that Fibonacci(h) mod 3 = 0.
Cf. A047443: numbers h such that Fibonacci(h) mod 3 = 2.
Sequence in context: A323528 A073074 A034796 * A221280 A166570 A003668
Adjacent sequences: A047523 A047524 A047525 * A047527 A047528 A047529


KEYWORD

nonn,easy


AUTHOR

N. J. A. Sloane


STATUS

approved



