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A047486

Numbers that are congruent to {0, 1, 3, 5, 7} mod 8.

0, 1, 3, 5, 7, 8, 9, 11, 13, 15, 16, 17, 19, 21, 23, 24, 25, 27, 29, 31, 32, 33, 35, 37, 39, 40, 41, 43, 45, 47, 48, 49, 51, 53, 55, 56, 57, 59, 61, 63, 64, 65, 67, 69, 71, 72, 73, 75, 77, 79, 80, 81, 83, 85, 87, 88, 89

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OFFSET

1,3

COMMENTS

Also nonnegative integers primitively represented by x^2 - y^2. - Ray Chandler, Aug 23 2014

LINKS

Ray Chandler, Table of n, a(n) for n = 1..10000

N. J. A. Sloane et al., Binary Quadratic Forms and OEIS (Index to related sequences, programs, references)

Index entries for linear recurrences with constant coefficients, signature (1,0,0,0,1,-1).

FORMULA

G.f.: x^2*(x^2 + 1)*(1 + x)^2/((x^4 + x^3 + x^2 + x + 1)*(x - 1)^2). - R. J. Mathar, Oct 07 2011

From Wesley Ivan Hurt, Dec 28 2016: (Start)

a(n) = a(n-1) + a(n-5) - a(n-6) for n > 6.

a(n) = (40*n - 40 - 2*(n mod 5) - 2*((n+1) mod 5) - 2*((n+2) mod 5) + 3*((n+3) mod 5) + 3*((n+4) mod 5))/25. (End)

CROSSREFS

Cf. A065091, A094572.

Sequence in context: A295075 A184996 A153309 * A229838 A191257 A120212

Adjacent sequences: A047483 A047484 A047485 * A047487 A047488 A047489

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane

STATUS

approved