A110760 a(n) = number of divisors of the concatenation of n,n-1,...3,2,1,2,3,...,n-1,n.

1, 6, 8, 4, 32, 28, 8, 16, 8, 8, 8, 16, 2, 16, 64, 6, 4, 8, 16, 384, 16, 256, 4, 12, 24, 64, 32, 256, 32, 64, 64, 12, 32, 128, 16, 80, 256, 32, 96, 96, 8, 8, 128, 256, 128, 128, 1024, 192, 64, 96, 128, 64, 32, 32, 128

Offset

1,2

Links

Table of n, a(n) for n=1..55.

Formula

a(n) = A000005(A007942(n)). - Michel Marcus, Mar 22 2023

Example

a(3) = tau(32123) = 8.

Crossrefs

Cf. A000005, A007942, A110756, A110757, A110758, A110759.

Sequence in context: A347407 A065166 A006255 * A050710 A123092 A209283

Adjacent sequences: A110757 A110758 A110759 * A110761 A110762 A110763

Keyword

base,more,nonn

Author

Amarnath Murthy, Aug 11 2005

Extensions

More terms from Ryan Propper, Jul 21 2006

Corrected and extended by Tyler Busby, Feb 12 2023

a(45)-a(55) from Tyler Busby, Feb 26 2023

Status

approved