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A103463 Length of the largest left-truncatable prime (in base n). 4
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 (list; graph; refs; listen; history; text; internal format)
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]

REFERENCES

Angell, I. O.; Godwin, H. J.: On Truncatable Primes. Mathematics of Computation vol. 31 (1977), no. 137, pp. 265-267.

LINKS

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

Index entries for sequences related to truncatable primes

Martin Renner, Table of n, a(n) for n = 2..53 (with some question marks)

Eric Weisstein: Truncatable Prime.

CROSSREFS

Cf. A076623, A103443.

Sequence in context: A238775 A269525 A036252 * A265026 A223048 A181372

Adjacent sequences:  A103460 A103461 A103462 * A103464 A103465 A103466

KEYWORD

nonn,base

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

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Last modified November 18 10:38 EST 2017. Contains 294887 sequences.