OFFSET
0,2
COMMENTS
This is column 1 of the transposable interspersion A283938.
LINKS
Clark Kimberling, Table of n, a(n) for n = 0..1000
FORMULA
a(n) = n + 1 + Sum_{k=0..n} floor((n-k)/r), where r = (3+sqrt(5))/2.
MATHEMATICA
PROG
(PARI) a(n) = if(n<1, 1, a(n - 1) + 1 + floor(n*(3 + sqrt(5))/2));
for(n = 0, 50, print1(a(n), ", ")) \\ Indranil Ghosh, Mar 19 2017
(Python)
import math
from sympy import sqrt
def a(n):
return 1 if n<1 else a(n - 1) + 1 + int(math.floor(n*(3 + sqrt(5))/2))
print([a(n) for n in range(51)]) # Indranil Ghosh, Mar 19 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Mar 18 2017
STATUS
approved