A053794 a(n) = (n^2 + n) modulo 8.

0, 2, 6, 4, 4, 6, 2, 0, 0, 2, 6, 4, 4, 6, 2, 0, 0, 2, 6, 4, 4, 6, 2, 0, 0, 2, 6, 4, 4, 6, 2, 0, 0, 2, 6, 4, 4, 6, 2, 0, 0, 2, 6, 4, 4, 6, 2, 0, 0, 2, 6, 4, 4, 6, 2, 0, 0, 2, 6, 4, 4, 6, 2, 0, 0, 2, 6, 4, 4, 6, 2, 0, 0, 2, 6, 4, 4, 6, 2, 0, 0, 2, 6, 4, 4, 6, 2, 0, 0, 2, 6, 4, 4, 6, 2, 0, 0, 2, 6, 4, 4, 6, 2, 0

Offset

0,2

Comments

Periodic with period 8.

Links

Antti Karttunen, Table of n, a(n) for n = 0..8191

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

Formula

From Wesley Ivan Hurt, Jun 22 2022: (Start)

a(n) = 2*A105198(n).

a(n) = a(n-1)-a(n-2)+a(n-3)-a(n-4)+a(n-5)-a(n-6)+a(n-7). (End)

Mathematica

PadRight[{}, 105, {0, 2, 6, 4, 4, 6, 2, 0}] (* Michael De Vlieger, Jun 22 2022 *)

Prog

(PARI) A053794(n)=[0, 2, 6, 4, 4, 6, 2, 0][n%8+1] \\ M. F. Hasler, Aug 27 2012
(Scheme) (define (A053794 n) (modulo (+ (* n n) n) 8)) ;; Antti Karttunen, Aug 10 2017

Crossrefs

Cf. A053793, A105198.

Sequence in context: A187817 A276678 A276680 * A249913 A003077 A323482

Adjacent sequences: A053791 A053792 A053793 * A053795 A053796 A053797

Keyword

nonn,easy

Author

Stuart M. Ellerstein (ellerstein(AT)aol.com), Mar 27 2000

Extensions

More terms from James A. Sellers, Apr 08 2000

Extended to n=103 by Antti Karttunen, Aug 10 2017

Status

approved