OFFSET
1,2
LINKS
Colin Barker, Table of n, a(n) for n = 1..399
Index entries for linear recurrences with constant coefficients, signature (1,103682,-103682,-1,1).
FORMULA
a(n) = a(n-1)+103682*a(n-2)-103682*a(n-3)-a(n-4)+a(n-5).
G.f.: -x*(x^4+4140*x^3-22538*x^2+4140*x+1) / ((x-1)*(x^2-322*x+1)*(x^2+322*x+1)).
EXAMPLE
4141 is in the sequence because it is the 41st heptagonal number and the 46th centered square number.
PROG
(PARI) Vec(-x*(x^4+4140*x^3-22538*x^2+4140*x+1)/((x-1)*(x^2-322*x+1)*(x^2+322*x+1)) + O(x^100))
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Colin Barker, Jan 27 2015
STATUS
approved