A105452 Numerator of (7 n -1)/3.
2, 13, 20, 9, 34, 41, 16, 55, 62, 23, 76, 83, 30, 97, 104, 37, 118, 125, 44, 139, 146, 51, 160, 167, 58, 181, 188, 65, 202, 209, 72, 223, 230, 79, 244, 251, 86, 265, 272, 93, 286, 293, 100, 307, 314, 107, 328, 335, 114, 349
Offset: 1
Links
- Index entries for linear recurrences with constant coefficients, signature (0,0,2,0,0,-1).
Formula
a(3*n+1) = 7*n+2 = A017005(n), a(3*n+2) = 2*n+13, a(3*n+3) = 21*n+20.
From Chai Wah Wu, Sep 24 2020: (Start)
a(n) = 2*a(n-3) - a(n-6) for n > 6.
G.f.: x*(x^5 + 8*x^4 + 5*x^3 + 20*x^2 + 13*x + 2)/(x^6 - 2*x^3 + 1). (End)