A133361 Multiply by 9 and reverse.

1, 9, 18, 261, 9432, 88848, 236997, 3792312, 80803143, 782822727, 3454045407, 36680468013, 711212421033, 7929871190046, 41401704886317, 358679343516273, 7546461904118223, 70046073175181976, 487736675856414036, 4236277072800369834, 60582330255639462183

Offset: 1

Author

Rachit Agrawal (rachit_agrawal(AT)daiict.ac.in), Oct 26 2007

Keywords

• base
• nonn

Links

• Alois P. Heinz, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A036447 (*2), A163632 (*3), A132064 (*4), A045539 (*5), A132078 (*6), A132114 (*7), A132113 (*8).

Programs

Maple

a:= proc(n) option remember; `if`(n=1, 1,
      (s-> parse(cat(s[-i]$i=1..length(s))))(""||(9*a(n-1))))
    end:
seq(a(n), n=1..25);  # Alois P. Heinz, Apr 09 2015

Mathematica

a[n_] := a[n] = If[n==1, 1, IntegerReverse[9a[n-1]]];
a /@ Range[40] (* Jean-François Alcover, Jan 01 2021 *)

Formula

a(n) = reverse(9*a(n-1)) where a(1) = 1.

Conjecture: a(n)^(1/n) tends to 10. - Vaclav Kotesovec, Jan 03 2020

Extensions

More terms from Alois P. Heinz, Apr 09 2015