A132113 Multiply previous term by 8 and reverse.

1, 8, 46, 863, 4096, 86723, 487396, 8619983, 46895986, 888761573, 4852900117, 63900232883, 460368102115, 296184492863, 4092495749632, 65079956993723, 487949556936025, 28845546953093, 447426573467032, 6526377852149753

Offset

1,2

Links

Vaclav Kotesovec, Table of n, a(n) for n = 1..1000

Formula

a(n) = reverse(8 * a(n-1)) where a(1) = 1.

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

Example

a(4) = reverse(8 * a(3))
= reverse(8 * reverse(8 * a(2)))
= reverse(8 * reverse(8 * reverse(8 * a(1))))
= reverse(8 * reverse(8 * reverse(8)))
= reverse(8 * reverse(8 * 8))
= reverse(8 * 46)
= reverse(368)
= 863.

Maple

rev:=proc(n) local nn: nn:=convert(n, base, 10): add(nn[j]*10^(nops(nn)-j), j = 1..nops(nn)) end proc: a[1]:=1: for n from 2 to 20 do a[n]:=rev(8*a[n-1]) end do: seq(a[n], n=1..20); # Definition corrected by Emeric Deutsch, Nov 07 2007

Mathematica

NestList[IntegerReverse[8#]&, 1, 20] (* Harvey P. Dale, Dec 22 2018 *)

Crossrefs

Cf. A036447 (*2), A163632 (*3), A132064 (*4), A045539 (*5), A132078 (*6), A132114 (*7), A133361 (*9).

Sequence in context: A141788 A317224 A368269 * A085299 A160640 A230622

Adjacent sequences: A132110 A132111 A132112 * A132114 A132115 A132116

Keyword

base,nonn

Author

Rachit Agrawal (rachit_agrawal(AT)daiict.ac.in), Oct 31 2007

Extensions

Definition corrected by Emeric Deutsch, Nov 07 2007

Edited by Jon E. Schoenfield, May 10 2019

Status

approved