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A100475
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Prime-th recurrence with reversal at each step.
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0
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1, 2, 3, 5, 11, 13, 14, 34, 931, 7037, 95017, 3549221, 75296795, 3518502151, 34778126848, 747746329129, 13428156340222, 728260738568834, 17205012007789762
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OFFSET
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0,2
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COMMENTS
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Starting at other than a(n) = 1, does this sequence ever go into a loop?
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REFERENCES
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Ball, W. W. R. and Coxeter, H. S. M. Mathematical Recreations and Essays, 13th ed. New York: Dover, pp. 14-15, 1987.
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LINKS
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Eric Weisstein's World of Mathematics, Reversal.
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FORMULA
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a(n) = reversal(a(n-1)th prime).
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EXAMPLE
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a(7) = 14 because a(6) = 13, the 13th prime is 41 and reversal(41) = 14.
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MATHEMATICA
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f[n_] := FromDigits[ Reverse[ IntegerDigits[ Prime[n]]]]; NestList[f, 1, 16] (* Robert G. Wilson v, Dec 02 2004 *)
NestList[IntegerReverse[Prime[#]]&, 1, 19] (* Harvey P. Dale, May 02 2022 *)
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CROSSREFS
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KEYWORD
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nonn,base,more
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AUTHOR
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EXTENSIONS
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a(17)-a(18) from Paul Zimmermann, Dec 04 2004, computed thanks to Deléglise-Rivat's program; confirmed by Marc Deléglise, Dec 09 2004
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STATUS
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approved
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