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A055521 Restricted left truncatable (Henry VIII) primes. 2
773, 3373, 3947, 4643, 5113, 6397, 6967, 7937, 15647, 16823, 24373, 33547, 34337, 37643, 56983, 57853, 59743, 62383, 63347, 63617, 69337, 72467, 72617, 75653, 76367, 87643, 92683, 97883, 98317, 121997, 124337, 163853, 213613, 236653 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

There are 1440 such primes, the largest being 357686312646216567629137.

Left-truncatable primes (A024785) which have at least two digits and are not the end of a larger left-truncatable prime. - Jens Kruse Andersen, Jul 29 2014

REFERENCES

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

Kahan, S. and Weintraub, S. "Left Truncatable Primes." J. Recr. Math. 29, 254-264, 1998.

LINKS

Jens Kruse Andersen, Table of n, a(n) for n = 1..1440 (complete sequence)

Eric Weisstein's World of Mathematics, Truncatable Prime

Index entries for sequences related to truncatable primes

EXAMPLE

773 is in the sequence since 773, 73, 3 are primes, while no digit 1..9 gives a prime if placed before 773. 13 is not in the sequence since for example 113 is prime. 2 and 5 are disqualified for only having one digit. - Jens Kruse Andersen, Jul 29 2014

CROSSREFS

Cf. A024785.

Sequence in context: A133963 A133964 A033919 * A233991 A077077 A177845

Adjacent sequences:  A055518 A055519 A055520 * A055522 A055523 A055524

KEYWORD

nonn,base,fini,full

AUTHOR

Eric W. Weisstein

STATUS

approved

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Last modified October 24 16:46 EDT 2014. Contains 248516 sequences.