login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

Thanks to everyone who made a donation during our annual appeal!
To see the list of donors, or make a donation, see the OEIS Foundation home page.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A047369 Numbers that are congruent to {1, 2, 3, 4, 5} mod 7. 1
1, 2, 3, 4, 5, 8, 9, 10, 11, 12, 15, 16, 17, 18, 19, 22, 23, 24, 25, 26, 29, 30, 31, 32, 33, 36, 37, 38, 39, 40, 43, 44, 45, 46, 47, 50, 51, 52, 53, 54, 57, 58, 59, 60, 61, 64, 65, 66, 67, 68, 71, 72, 73, 74, 75, 78, 79, 80, 81, 82, 85, 86, 87, 88, 89, 92 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

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

FORMULA

G.f.: x*(1+x+x^2+x^3+x^4+2*x^5) / ( (x^4+x^3+x^2+x+1)*(x-1)^2 ). - R. J. Mathar, Dec 04 2011

From Wesley Ivan Hurt, Aug 08 2016: (Start)

a(n) = a(n-1) + a(n-5) - a(n-6) for n > 6, a(n) = a(n-5) + 7 for n > 5.

a(n) = n + 2*floor((n-1)/5), a(n) = 7*n/5 - 2*(1 + ((n+4) mod 5))/5.

a(5*k) = 7*k-2, a(5*k-1) = 7*k-3, a(5*k-2) = 7*k-4, a(5*k-3) = 7*k-5, a(5*k-4) = 7*k-6. (End)

MAPLE

A047369:=n->7*floor(n/5)+[(1, 2, 3, 4, 5)][(n mod 5)+1]: seq(A047369(n), n=0..100); # Wesley Ivan Hurt, Aug 08 2016

MATHEMATICA

Select[Range[0, 100], MemberQ[{1, 2, 3, 4, 5}, Mod[#, 7]] &] (* Wesley Ivan Hurt, Aug 08 2016 *)

LinearRecurrence[{1, 0, 0, 0, 1, -1}, {1, 2, 3, 4, 5, 8}, 100] (* Vincenzo Librandi, Aug 08 2016 *)

PROG

(MAGMA) [n : n in [0..150] | n mod 7 in [1..5]]; // Wesley Ivan Hurt, Aug 08 2016

CROSSREFS

Sequence in context: A288666 A180734 A031482 * A004827 A155941 A046892

Adjacent sequences:  A047366 A047367 A047368 * A047370 A047371 A047372

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 20 14:02 EST 2020. Contains 331094 sequences. (Running on oeis4.)