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A112691
a(n) = J(n+1) mod J(n), J(n)=A001045(n).
1
1, 0, 0, 2, 1, 10, 1, 42, 1, 170, 1, 682, 1, 2730, 1, 10922, 1, 43690, 1, 174762, 1, 699050, 1, 2796202, 1, 11184810, 1, 44739242, 1, 178956970, 1, 715827882, 1, 2863311530, 1, 11453246122, 1, 45812984490, 1, 183251937962, 1, 733007751850, 1, 2932031007402
OFFSET
0,4
FORMULA
G.f.: x*(1-5*x^2+2*x^3+5*x^4-4*x^6) / (1-5*x^2+4*x^4).
a(2*n) = 1 - C(1, n) + C(0, n); a(2*n+1) = 2*A002450(n).
From Colin Barker, Apr 21 2017: (Start)
a(n) = (1 - (-2)^n + 5*(-1)^n + 2^n) / 6 for n>2.
a(n) = 5*a(n-2) - 4*a(n-4) for n>4.
(End)
MATHEMATICA
LinearRecurrence[{0, 5, 0, -4}, {1, 0, 0, 2, 1, 10, 1}, 50] (* Harvey P. Dale, Oct 04 2018 *)
PROG
(PARI) Vec((1 - 5*x^2 + 2*x^3 + 5*x^4 - 4*x^6) / ((1 - x)*(1 + x)*(1 - 2*x)*(1 + 2*x)) + O(x^30)) \\ Colin Barker, Apr 21 2017
CROSSREFS
Sequence in context: A105606 A132995 A114692 * A110169 A144274 A144275
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Sep 15 2005
STATUS
approved