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A125135 Triangle read by rows in which row n gives list of prime factors of p^p - 1 where p = prime(n). 3
3, 2, 13, 2, 2, 11, 71, 2, 3, 29, 4733, 2, 5, 15797, 1806113, 2, 2, 3, 53, 264031, 1803647, 2, 2, 2, 2, 10949, 1749233, 2699538733, 2, 3, 3, 109912203092239643840221, 2, 11, 461, 1289, 831603031789, 1920647391913 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

LINKS

Sam Wagstaff, Factorizations of p^p - 1 for most p < 180

EXAMPLE

Triangle begins:

3

2*13

2*2*11*71

2*3*29*4733

2*5*15797*1806113

2*2*3*53*264031*1803647

2*2*2*2^10949*1749233^2699538733

2*3*3*109912203092239643840221

2*11*461*1289*831603031789^1920647391913

2*2*7*59*16763*84449*2428577*14111459*58320973*549334763

n=4: p=7, 7^7-1 = 823542 = 2*3*29*4733 gives row 4.

PROG

(MAGMA) for p in [ n : n in [1..100] | IsPrime(n) ] do "\nDoing p =", p; n := p^p -1; Factorisation(n); end for; [From John Cannon]

CROSSREFS

Cf. A088730, A125136.

Sequence in context: A007214 A189736 A025232 * A055456 A198303 A093922

Adjacent sequences:  A125132 A125133 A125134 * A125136 A125137 A125138

KEYWORD

nonn,tabf

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), Jan 21 2007

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Last modified February 14 14:47 EST 2012. Contains 205623 sequences.