|
|
A187331
|
|
a(n) = Sum_{k=1..4} floor(k*n/4).
|
|
2
|
|
|
0, 1, 4, 6, 10, 11, 14, 16, 20, 21, 24, 26, 30, 31, 34, 36, 40, 41, 44, 46, 50, 51, 54, 56, 60, 61, 64, 66, 70, 71, 74, 76, 80, 81, 84, 86, 90, 91, 94, 96, 100, 101, 104, 106, 110, 111, 114, 116, 120, 121, 124, 126, 130, 131, 134, 136, 140, 141, 144, 146, 150, 151, 154, 156, 160, 161, 164
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,3
|
|
LINKS
|
|
|
FORMULA
|
a(n) = a(n-1) + a(n-4) - a(n-5) for n > 4.
G.f.: x*(4*x^3 + 2*x^2 + 3*x + 1)/(x^5 - x^4 - x + 1). (End)
|
|
MATHEMATICA
|
t=Table[Sum[Floor[k*n/4], {k, 1, 4}], {n, 0, 200}] (* A187331 *)
Complement[Range[Length[t]], t] (* A187332 *)
|
|
PROG
|
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|