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A153990 Period 6: repeat [1, 2, 5, 4, 7, 8]. 4
1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Shares digits with other 6-periodic sequences, see the list in A153130.

Also the decimal expansion of the constant 13942/111111. [R. J. Mathar, Jan 23 2009]

Terms of the simple continued fraction of 485/(sqrt(4579599)-1807). [Paolo P. Lava, Feb 17 2009]

LINKS

Table of n, a(n) for n=0..85.

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

FORMULA

a(n) - A141425(n) = A131533(n+2).

a(6n+0) + a(6n+5) = a(6n+1) + a(6n+4) = a(6n+2) + a(6n+3) = 9.

a(n) = (1/15)*{22*(n mod 6)+2*[(n+1) mod 6]-3*[(n+2) mod 6]+7*[(n+3) mod 6]-3*[(n+4) mod 6]+2*[(n+5) mod 6]}. [Paolo P. Lava, Jan 09 2009]

G.f.: (1+2*x+5*x^2+4*x^3+7*x^4+8*x^5)/((1-x)*(1+x)*(1+x+x^2)*(x^2-x+1)). [R. J. Mathar, Jan 23 2009]

From Wesley Ivan Hurt, Jun 17 2016: (Start)

a(n) = (27-cos(n*Pi)-8*sqrt(3)*cos((1-4*n)*Pi/6)-16*sin((1+2*n)*Pi/6))/6.

a(n) = a(n-6) for n>5. (End)

MAPLE

A153990:=n->(27-cos(n*Pi)-8*sqrt(3)*cos((1-4*n)*Pi/6)-16*sin((1+2*n)*Pi/6))/6: seq(A153990(n), n=0..100); # Wesley Ivan Hurt, Jun 17 2016

MATHEMATICA

Flatten[Table[{1, 2, 5, 4, 7, 8}, {20}]] (* Wesley Ivan Hurt, Jun 17 2016 *)

PadRight[{}, 120, {1, 2, 5, 4, 7, 8}] (* Harvey P. Dale, Nov 08 2017 *)

PROG

(MAGMA) &cat[[1, 2, 5, 4, 7, 8]: n in [0..20]]; // Wesley Ivan Hurt, Jun 17 2016

CROSSREFS

Cf. A131533, A141425, A153130, A154811.

Sequence in context: A171760 A085801 A023843 * A154811 A296203 A036237

Adjacent sequences:  A153987 A153988 A153989 * A153991 A153992 A153993

KEYWORD

nonn,easy

AUTHOR

Paul Curtz, Jan 04 2009

EXTENSIONS

Edited by R. J. Mathar, Jan 23 2009

STATUS

approved

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Last modified March 24 06:56 EDT 2019. Contains 321444 sequences. (Running on oeis4.)