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A132114
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Multiply previous term by 7 and reverse.
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8
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1, 7, 94, 856, 2995, 56902, 413893, 1527982, 47859601, 702710533, 1373798194, 8537856169, 38139946795, 565726979662, 4367588800693, 15840612137503, 125269482488011, 770614773688678, 6470285143034935, 54544210069919254
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OFFSET
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1,2
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LINKS
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FORMULA
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a(n) = reverse(7 * a(n-1)) with a(1) = 1.
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EXAMPLE
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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.
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PROG
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(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
(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
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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Rachit Agrawal (rachit_agrawal(AT)daiict.ac.in), Oct 31 2007
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EXTENSIONS
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STATUS
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approved
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