OFFSET
0,5
LINKS
Colin Barker, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (2,-1,0,0,0,0,0,0,0,0,1,-2,1).
FORMULA
a(n) = +2 a(n-1) -a(n-2) +a(n-11) -2 a(n-12) +a(n-13). - R. J. Mathar, Mar 11 2012
G.f.: x*(1+x)*(1-x+x^2)*(1-x+x^2-x^3+x^4)*(1-x^2+x^4) / ((1-x)^3*(1+x+x^2+x^3+x^4+x^5+x^6+x^7+x^8+x^9+x^10)). - Colin Barker, Apr 06 2016
a(m + 11 k) = a(m) + 11 k^2 + 2 m k. - Robert Israel, Apr 06 2016
MAPLE
seq(ceil(n^2/11), n=0..100); # Robert Israel, Apr 06 2016
MATHEMATICA
Table[Ceiling[n^2/11], {n, 0, 57}] (* Michael De Vlieger, Apr 06 2016 *)
LinearRecurrence[{2, -1, 0, 0, 0, 0, 0, 0, 0, 0, 1, -2, 1}, {0, 1, 1, 1, 2, 3, 4, 5, 6, 8, 10, 11, 14}, 60] (* Harvey P. Dale, Aug 29 2021 *)
PROG
(PARI) concat(0, Vec(x*(1+x)*(1-x+x^2)*(1-x+x^2-x^3+x^4)*(1-x^2+x^4) / ((1-x)^3*(1+x+x^2+x^3+x^4+x^5+x^6+x^7+x^8+x^9+x^10)) + O(x^50))) \\ Colin Barker, Apr 06 2016
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved