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A140724 Period 10: 1, 5, 9, 7, 7, 9, 5, 1, 3, 3 repeated. 1
1, 5, 9, 7, 7, 9, 5, 1, 3, 3, 1, 5, 9, 7, 7, 9, 5, 1, 3, 3, 1, 5, 9, 7, 7, 9, 5, 1, 3, 3, 1, 5, 9, 7, 7, 9, 5, 1, 3, 3, 1, 5, 9, 7, 7, 9, 5, 1, 3, 3, 1, 5, 9, 7, 7, 9, 5, 1, 3, 3, 1, 5, 9, 7, 7, 9, 5, 1, 3, 3, 1, 5, 9, 7, 7, 9, 5, 1, 3, 3, 1, 5, 9, 7, 7, 9, 5, 1, 3, 3, 1, 5, 9, 7, 7, 9, 5, 1, 3, 3, 1, 5, 9, 7, 7 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

The last digit of A108981(n).

Also the continued fraction of (290003+sqrt(240183699293))/652402.

Also the decimal expansion of 13073/81819.

The period contains each of the 5 odd digits twice.

LINKS

Table of n, a(n) for n=0..104.

Index entries for linear recurrences with constant coefficients, signature (2,-2,2,-2,1).

FORMULA

a(n)+a(n+5) = 10 = A010692(n).

a(n) = a(n+10) .

a(10*k+9+i) = a(10*k+18-i) (palindromic).

a(n) = 2*a(n-1)-2*a(n-2)+2*a(n-3)-2*a(n-4)+a(n-5). G.f.: -(1+3*x+x^2-3*x^3+3*x^4)/ ((x-1) * (x^4-x^3+x^2-x+1)).

a(n)=(1/45)*{14*(n mod 10)+5*[(n+1) mod 10]-4*[(n+2) mod 10]+23*[(n+3) mod 10]+23*[(n+4) mod 10]-4*[(n+5) mod 10]+5*[(n+6) mod 10]+14*[(n+7) mod 10]-13*[(n+8) mod 10]-13*[(n+9) mod 10]}, with n>=0 - Paolo P. Lava, Jul 14 2008

PROG

(PARI) 13073/81819. \\ Charles R Greathouse IV, Jul 21 2015

CROSSREFS

Sequence in context: A220261 A195285 A200597 * A086055 A219734 A077125

Adjacent sequences:  A140721 A140722 A140723 * A140725 A140726 A140727

KEYWORD

nonn,easy

AUTHOR

Paul Curtz, Jul 12 2008

EXTENSIONS

Edited by R. J. Mathar, Sep 07 2009

STATUS

approved

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Last modified February 22 23:03 EST 2019. Contains 320411 sequences. (Running on oeis4.)