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A047455 Numbers that are congruent to {2, 3, 4} mod 8. 1
2, 3, 4, 10, 11, 12, 18, 19, 20, 26, 27, 28, 34, 35, 36, 42, 43, 44, 50, 51, 52, 58, 59, 60, 66, 67, 68, 74, 75, 76, 82, 83, 84, 90, 91, 92, 98, 99, 100, 106, 107, 108, 114, 115, 116, 122, 123, 124, 130, 131, 132, 138, 139, 140, 146, 147, 148, 154, 155, 156 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..60.

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

FORMULA

G.f.: x*(2+x+x^2+4*x^3)/((1-x)^2*(1+x+x^2)). [Colin Barker, May 13 2012]

From Wesley Ivan Hurt, Jun 09 2016: (Start)

a(n) = a(n-1) + a(n-3) - a(n-4) for n>4.

a(n) = (24*n-21-15*cos(2*n*Pi/3)+5*sqrt(3)*sin(2*n*Pi/3))/9.

a(3k) = 8k-4, a(3k-1) = 8k-5, a(3k-2) = 8k-6. (End)

MAPLE

A047455:=n->(24*n-21-15*cos(2*n*Pi/3)+5*sqrt(3)*sin(2*n*Pi/3))/9: seq(A047455(n), n=1..100); # Wesley Ivan Hurt, Jun 09 2016

MATHEMATICA

Select[Range[150], MemberQ[{2, 3, 4}, Mod[#, 8]]&] (* or *) Flatten[#+{2, 3, 4}&/@(8Range[0, 20])] (* Harvey P. Dale, Oct 09 2012 *)

PROG

(MAGMA) [n : n in [0..150] | n mod 8 in [2..4]]; // Wesley Ivan Hurt, Jun 09 2016

CROSSREFS

Sequence in context: A058185 A080897 A117383 * A202426 A039002 A120023

Adjacent sequences:  A047452 A047453 A047454 * A047456 A047457 A047458

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified December 5 05:27 EST 2016. Contains 278761 sequences.