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A199428 Extreme weakly prime numbers. 1
40144044691, 58058453543, 89797181359, 185113489357, 213022025663, 222498988079, 365115312521, 397195264507, 507086259359, 537598896647, 576872778883, 671770400281, 710587610861, 719174481061, 815380174991, 840202011349, 855194972407, 869287849361, 891600776149 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes that become composite if any digit is removed, changed, or inserted anywhere. First & smallest  term found by Jens K. Andersen in 2008; five more by Giovanni Resta in Nov. 2011. Expected infinite of them. These primes emerge in relation to the prime-version of classical Doublets puzzle by Lewis Carrol. Correspond to the "aloof" words as named by Donald Knuth.

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..50

G. L. Honaker, Jr. and C. K. Caldwell, Prime Curios! 40144044691

C. Rivera, The prime puzzles & problems connection, puzzle 612

Wikipedia, Word ladder

CROSSREFS

Cf. A050249.

Sequence in context: A216018 A256842 A225886 * A287261 A172631 A172721

Adjacent sequences:  A199425 A199426 A199427 * A199429 A199430 A199431

KEYWORD

nonn,base

AUTHOR

Carlos Rivera, Nov 06 2011

EXTENSIONS

More terms from Giovanni Resta, Aug 15 2019

STATUS

approved

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Last modified March 4 05:41 EST 2021. Contains 341779 sequences. (Running on oeis4.)