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%I #14 Sep 08 2022 08:45:31
%S 1,7,94,856,2995,56902,413893,1527982,47859601,702710533,1373798194,
%T 8537856169,38139946795,565726979662,4367588800693,15840612137503,
%U 125269482488011,770614773688678,6470285143034935,54544210069919254
%N Multiply previous term by 7 and reverse.
%H Vaclav Kotesovec, <a href="/A132114/b132114.txt">Table of n, a(n) for n = 1..1000</a>
%H Vaclav Kotesovec, <a href="/A132114/a132114.jpg">Plot of a(n)^(1/n) for n = 1..10000</a>
%F a(n) = reverse(7 * a(n-1)) with a(1) = 1.
%e a(4) = reverse(7 * a(3)) = reverse(7 * reverse(7 * a(2))) = reverse(7 * reverse(7 * reverse(7 * a(1)))) = reverse(7 * reverse(7 * reverse(7))) = reverse(7*94) = 856.
%o (PARI) seq(n)={my(a=vector(n)); a[1]=1; for(n=2, #a, a[n]=fromdigits(Vecrev(digits(a[n-1]*7)))); a} \\ _Andrew Howroyd_, Jan 02 2020
%o (Magma) f:=func<n|Seqint(Reverse(Intseq(7*n)))>; a:=[1]; for n in [2..20] do Append(~a,f(a[n-1])); end for; a; // _Marius A. Burtea_, Jan 03 2020
%Y Cf. A036447 (*2), A163632 (*3), A132064 (*4), A045539 (*5), A132078 (*6), A132113 (*8), A133361 (*9).
%K base,nonn
%O 1,2
%A Rachit Agrawal (rachit_agrawal(AT)daiict.ac.in), Oct 31 2007
%E Name edited by _Andrew Howroyd_, Jan 02 2020