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a(n) = number of divisors of the concatenation of n,n-1,...3,2,1,2,3,...,n-1,n.
6

%I #36 Mar 22 2023 10:52:45

%S 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,

%T 32,256,32,64,64,12,32,128,16,80,256,32,96,96,8,8,128,256,128,128,

%U 1024,192,64,96,128,64,32,32,128

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

%F a(n) = A000005(A007942(n)). - _Michel Marcus_, Mar 22 2023

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

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

%K base,more,nonn

%O 1,2

%A _Amarnath Murthy_, Aug 11 2005

%E More terms from _Ryan Propper_, Jul 21 2006

%E Corrected and extended by _Tyler Busby_, Feb 12 2023

%E a(45)-a(55) from _Tyler Busby_, Feb 26 2023