A067761 Positive integers divisible by 5 but not by 7.

5, 10, 15, 20, 25, 30, 40, 45, 50, 55, 60, 65, 75, 80, 85, 90, 95, 100, 110, 115, 120, 125, 130, 135, 145, 150, 155, 160, 165, 170, 180, 185, 190, 195, 200, 205, 215, 220, 225, 230, 235, 240, 250, 255, 260, 265, 270, 275, 285, 290, 295, 300, 305, 310, 320

Offset: 1

Author

Jonathan A. Heese (macgyver86(AT)aol.com), Feb 06 2002

Keywords

• nonn
• easy

References

• Kenneth H. Rosen, Discrete Mathematics and Its Applications, 4th Ed., p. 79, 1.7.32.b.

Links

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

Crossrefs

Cf. A047304.

Programs

Mathematica

Select[Range[65]*5, Mod[5#, 7] != 0 &] (* corrected by Georg Fischer, Jun 17 2020 *)

Formula

a(n) = 5*A047304(n). - Zak Seidov, Mar 19 2014

a(n) = a(n - 6) + 35. - David A. Corneth, Jun 17 2020

G.f.: 5*x*(x^6+x^5+x^4+x^3+x^2+x+1)/(x^7-x^6-x+1). - Alois P. Heinz, Jun 17 2020

Extensions

Edited by Robert G. Wilson v, Feb 07 2002

a(36)=205 corrected by Georg Fischer, Jun 17 2020