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A110772 Beginning with 2, least number not occurring earlier such that every partial concatenation is prime. 1
2, 3, 9, 11, 13, 63, 51, 29, 69, 33, 49, 159, 17, 37, 39, 117, 53, 43, 47, 31, 23, 97, 171, 89, 367, 347, 157, 83, 447, 19, 249, 153, 233, 163, 141, 317, 471, 391, 107, 93, 261, 339, 183, 87, 403, 129, 81, 173, 411, 57, 177, 109, 71, 121, 269, 609, 111, 1413, 99, 21 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Conjecture: every odd number not divisible by 5 is a member.

EXAMPLE

2,23,239,23911,2391113,... etc. are all prime.

MAPLE

L:=[2]: for n from 1 to 120 do for m from 1 do if isprime(parse(cat("", op(L), m))) and not member(m, L) then L:=[op(L), m]; break fi od od: L[]; (Mihailovs)

CROSSREFS

Cf. A110773, A089564.

Sequence in context: A140222 A121557 A138984 * A074338 A111319 A109658

Adjacent sequences:  A110769 A110770 A110771 * A110773 A110774 A110775

KEYWORD

easy,nonn,base

AUTHOR

Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Aug 12 2005

EXTENSIONS

More terms from Alec Mihailovs (alec(AT)mihailovs.com), Aug 14 2005

Edited by Charles R Greathouse IV (charles.greathouse(AT)case.edu), Apr 27 2010

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Last modified February 13 06:35 EST 2012. Contains 205451 sequences.