The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A125135 Triangle read by rows in which row n lists prime factors of p^p - 1 where p = prime(n). 8
 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; text; 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; // John Cannon CROSSREFS Cf. A006486, A088730, A125136. Sequence in context: A025232 A236435 A218566 * A055456 A198303 A093922 Adjacent sequences:  A125132 A125133 A125134 * A125136 A125137 A125138 KEYWORD nonn,tabf AUTHOR N. J. A. Sloane, Jan 21 2007 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified September 24 01:21 EDT 2020. Contains 337315 sequences. (Running on oeis4.)