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Multiply previous term by 8 and reverse.
8

%I #16 Jan 03 2020 04:54:05

%S 1,8,46,863,4096,86723,487396,8619983,46895986,888761573,4852900117,

%T 63900232883,460368102115,296184492863,4092495749632,65079956993723,

%U 487949556936025,28845546953093,447426573467032,6526377852149753

%N Multiply previous term by 8 and reverse.

%H Vaclav Kotesovec, <a href="/A132113/b132113.txt">Table of n, a(n) for n = 1..1000</a>

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

%F Conjecture: a(n)^(1/n) tends to 10. - _Vaclav Kotesovec_, Jan 03 2020

%e a(4) = reverse(8 * a(3))

%e = reverse(8 * reverse(8 * a(2)))

%e = reverse(8 * reverse(8 * reverse(8 * a(1))))

%e = reverse(8 * reverse(8 * reverse(8)))

%e = reverse(8 * reverse(8 * 8))

%e = reverse(8 * 46)

%e = reverse(368)

%e = 863.

%p 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

%t NestList[IntegerReverse[8#]&,1,20] (* _Harvey P. Dale_, Dec 22 2018 *)

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

%K base,nonn

%O 1,2

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

%E Definition corrected by _Emeric Deutsch_, Nov 07 2007

%E Edited by _Jon E. Schoenfield_, May 10 2019