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A047391 Numbers that are congruent to {1, 3, 5} mod 7. 2
1, 3, 5, 8, 10, 12, 15, 17, 19, 22, 24, 26, 29, 31, 33, 36, 38, 40, 43, 45, 47, 50, 52, 54, 57, 59, 61, 64, 66, 68, 71, 73, 75, 78, 80, 82, 85, 87, 89, 92, 94, 96, 99, 101, 103, 106, 108, 110, 113, 115, 117, 120, 122 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..53.

Index to sequences with linear recurrences with constant coefficients, signature (1,0,1,-1).

FORMULA

Contribution by Bruno Berselli, Mar 25 2011:  (Start)

G.f.: x*(1+2*x+2*x^2+2*x^3)/((1-x)^2*(1+x+x^2)).

a(n) = 7*floor((n-1)/3)+2*(n-1 mod 3)+1.

a(n) = (1/3)*(7*n-5-A049347(n)). (End)

PROG

(MAGMA) [ n: n in [1..122] | n mod 7 in [1, 3, 5] ];  // Bruno Berselli, Mar 25 2011

CROSSREFS

Sequence in context: A184584 A191160 A189929 * A184655 A090846 A195170

Adjacent sequences:  A047388 A047389 A047390 * A047392 A047393 A047394

KEYWORD

nonn

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified December 21 13:36 EST 2014. Contains 252321 sequences.