A175005 Expansion of x/(1 - 4*x + 3*x^2 - 2*x^3).

0, 1, 4, 13, 42, 137, 448, 1465, 4790, 15661, 51204, 167413, 547362, 1789617, 5851208, 19130705, 62548430, 204504021, 668632204, 2186113613, 7147565882, 23369187097, 76406277968, 249812682345, 816770269670, 2670455587581

Offset: 0

Author

Roger L. Bagula, Dec 02 2010

Keywords

• nonn
• easy

Comments

The limiting ratio a(n+1)/a(n) is 3.269530842081143....

Links

• Index entries for linear recurrences with constant coefficients, signature (4,-3,2).

Crossrefs

Cf. A000045, A174631, A000931, A111285.

Programs

PARI

Vec(x/(1-4*x+3*x^2-2*x^3)+O(x^99)) \\ Charles R Greathouse IV, Sep 26 2012

Formula

a(n) = 4*a(n-1) - 3*a(n-2) + 2*a(n-3), starting 0, 1, 4.