A103463 - OEIS

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A103463

Length of the largest left-truncatable prime (in base n).

0, 3, 6, 6, 17, 7, 15, 10, 24, 9, 32, 8, 26, 22, 25, 11, 43, 14, 37, 27, 37, 17, 53, 20, 39, 28, 46, 19

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OFFSET

2,2

COMMENTS

The next term (base 30) will be difficult to calculate because there are over a trillion left-truncatable primes in that base for each of digit-lengths 29-34. Nevertheless, the largest left-truncatable prime in this base can be estimated by theory to have a length of about 82. [Hans Havermann, Aug 16 2011]

LINKS

Table of n, a(n) for n=2..29.

I. O. Angell and H. J. Godwin, On Truncatable Primes, Math. Comput. 31, 265-267, 1977.

Roman Maeder, A Prime Pencil

Eric Weisstein's World of Mathematics, Truncatable Prime.

Index entries for sequences related to truncatable primes

CROSSREFS

Cf. A076623, A103443.

Sequence in context: A341885 A364372 A036252 * A370154 A265026 A304335

Adjacent sequences: A103460 A103461 A103462 * A103464 A103465 A103466

KEYWORD

nonn,base,more

AUTHOR

Martin Renner, Mar 21 2005, Feb 20 2008, Apr 20 2008

EXTENSIONS

a(24)-a(29) from Hans Havermann, Aug 16 2011

STATUS

approved