A147524 As a vector, shifts to the left when multiplied by A054521.

1, 1, 1, 2, 2, 5, 3, 12, 7, 21, 12, 55, 18, 122, 41, 171, 85, 474, 121, 1033, 248, 1479, 527, 3914, 769, 7258, 1817, 11637, 3401, 29836, 4168, 63073, 11221, 92425, 22357, 190248, 31464, 446565, 76142, 679451, 129236, 1680187, 169804, 3489610, 440212, 4451195

Offset: 1

Author

Gary W. Adamson, Apr 24 2009

Keywords

• nonn

Comments

Begin with (1, 1, 1), then the next term = dot product of current series and the corresponding row of A054521.

Eigensequence of triangle A054521.

Examples

			a(5) = 2 = (1, 1, 1, 2) dot (1, 0, 1, 0) = (1 + 0 + 1 + 0).
		

Crossrefs

Cf. A054521.

Programs

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

Extensions

Corrected and extended by Andrey Zabolotskiy, Aug 27 2024