OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..500
Index entries for linear recurrences with constant coefficients, signature (20,-108,144)
FORMULA
a(n) = A071951(n+3, 3) = (24*12^n - 15*6^n + 2^n)/10. - Wolfdieter Lang, Nov 07 2003
a(n) = 18*a(n-1) - 72*a(n-2) + 2^n; a(n) = 20*a(n-1) - 108*a(n-2) + 144*a(n-3) for n > 2. - Vincenzo Librandi, Sep 02 2011
a(n) = det(|ps(i+3,j+2)|, 1 <= i,j <= n), where ps(n,k) are Legendre-Stirling numbers of the first kind (A129467). - Mircea Merca, Apr 06 2013
MATHEMATICA
CoefficientList[Series[1/((1-2x)(1-6x)(1-12x)), {x, 0, 30}], x] (* or *) LinearRecurrence[{20, -108, 144}, {1, 20, 292}, 30] (* Harvey P. Dale, Jul 26 2019 *)
PROG
(Magma) [(24*12^n-15*6^n+2^n)/10: n in [0..20]]; // Vincenzo Librandi, Sep 02 2011
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved