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A131793 3 odds, 3 evens. 2
1, 3, 5, 2, 4, 6, 7, 9, 11, 8, 10, 12, 13, 15, 17, 14, 16, 18, 19, 21, 23, 20, 22, 24, 25, 27, 29, 26, 28, 30, 31, 33, 35, 32, 34, 36, 37, 39, 41, 38, 40, 42, 43, 45, 47, 44, 46, 48, 49, 51, 53, 50, 52, 54, 55, 57, 59, 56, 58, 60, 61, 63, 65, 62, 64, 66, 67, 69, 71, 68, 70, 72 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

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

FORMULA

a(n) = Sum_{k=0..n}{(1/30)*{7*(k mod 6)+2*[(k+1) mod 6]-23*[(k+2) mod 6]+27*[(k+3) mod 6]+2*[(k+4) mod 6]-3*[(k+5) mod 6]}} - Paolo P. Lava, Dec 19 2007

a(n) = 2*(3*floor((n-1)/6)+((n-1) mod 3)+1)-(floor((n+2)/3) mod 2) - Joshua Zucker, Aug 29 2012

G.f.: x*(1 + 2*x + 2*x^2 - 3*x^3 + 2*x^4 + 2*x^5)/(1 - x - x^6 + x^7). - Robert Israel, May 10 2020

MAPLE

f:= gfun:-rectoproc({a(n) = a(n-1)+a(n-6)-a(n-7), a(1)=1, a(2)=3, a(3)=5, a(4)=2, a(5)=4, a(6)=6, a(7)=7}, a(n), remember):

map(f, [$1..100]); # Robert Israel, May 10 2020

CROSSREFS

Sequence in context: A222601 A104807 A309492 * A065186 A210521 A219249

Adjacent sequences:  A131790 A131791 A131792 * A131794 A131795 A131796

KEYWORD

nonn

AUTHOR

Paul Curtz, Oct 23 2007

STATUS

approved

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Last modified June 4 08:18 EDT 2020. Contains 334825 sequences. (Running on oeis4.)