OFFSET
1,4
COMMENTS
EXAMPLE
a(5) = 2 = (1, 1, 1, 2) dot (1, 0, 1, 0) = (1 + 0 + 1 + 0).
PROG
(Python)
from math import gcd
a = [1]
for n in range (1, 45):
a.append(sum(a[k] for k in range(n) if gcd(k+1, n) == 1))
print(a) # Andrey Zabolotskiy, Aug 27 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
Gary W. Adamson, Apr 24 2009
EXTENSIONS
Corrected and extended by Andrey Zabolotskiy, Aug 27 2024
STATUS
approved