OFFSET
0,6
LINKS
Index entries for linear recurrences with constant coefficients, signature (3,-2,0,1,-3,2).
FORMULA
a(n) = a(n-4) + 2^(n-3) - 1.
a(n) = Sum_{k=0..n} floor(2^k/15).
a(n) = 3*a(n-1) - 2*a(n-2) + a(n-4) - 3*a(n-5) + 2*a(n-6).
G.f.: x^4/((1-x) * (1-2*x) * (1-x^4)).
a(n) = floor(2^(n+1)/15) - floor((n+1)/4).
PROG
(PARI) a(n, m=4, k=2) = (k^(n+1)\(k^m-1)-(n+1)\m)/(k-1);
(Python)
def A368346(n): return (1<<n+1)//15-(n+1>>2) # _Chai Wah Wu_, Dec 22 2023
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
_Seiichi Manyama_, Dec 22 2023
STATUS
approved