A110761 a(0) = 1; a(n+1) = tau(N) where N is the concatenation of a(0), a(1), a(2), a(3), ..., a(n).

1, 1, 2, 10, 16, 32, 72, 32, 112, 20, 96, 20, 144, 80, 80, 640, 288, 288, 48, 80, 80, 480, 384, 384, 512, 160, 768, 88, 64, 24, 128, 112, 20, 24, 128, 336, 80, 80, 640, 576, 112, 2560, 576, 1792, 36, 192, 12, 48, 3072, 320, 1792, 576, 2688

Offset

0,3

Links

Table of n, a(n) for n=0..52.

Example

a(0) = 1, a(1) = tau(1) = 1, a(2) = tau(11) = 2, a(3) = tau(112) = 10.

Maple

read("transforms") ;
A110761 := proc(n) option remember; local L ; if n = 0 then 1 ; else L := [seq(procname(i), i=0..n-1)] ; numtheory[tau]( digcatL(L)) ; end if; end proc: # R. J. Mathar, Apr 15 2011

Mathematica

aggluTau[0] := 1; aggluTau[n_] := aggluTau[n] = DivisorSigma[0, FromDigits[Flatten[Table[IntegerDigits[aggluTau[i]], {i, 0, n - 1}]]]]; aggluTau/@Range[0, 19] (* Alonso del Arte, Jan 10 2020 *)

Crossrefs

Cf. A000005 (tau).

Sequence in context: A341060 A189329 A242089 * A046036 A131474 A249153

Adjacent sequences: A110758 A110759 A110760 * A110762 A110763 A110764

Keyword

nonn,base,more

Author

Amarnath Murthy, Aug 11 2005

Extensions

a(22)-a(31) from Carl Najafi, Apr 15 2011

a(32)-a(49) from Chai Wah Wu, Dec 24 2019

a(50) from Chai Wah Wu, Jan 04 2020

a(51)-a(52) from Chai Wah Wu, Jan 08 2020

Status

approved