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A125135 Triangle read by rows in which row n lists prime factors of p^p - 1 where p = prime(n).

%I A125135 #20 Sep 08 2022 08:45:28
%S A125135 3,2,13,2,2,11,71,2,3,29,4733,2,5,15797,1806113,2,2,3,53,264031,
%T A125135 1803647,2,2,2,2,10949,1749233,2699538733,2,3,3,
%U A125135 109912203092239643840221,2,11,461,1289,831603031789,1920647391913
%N A125135 Triangle read by rows in which row n lists prime factors of p^p - 1 where p = prime(n).
%H A125135 Sam Wagstaff, <a href="http://homes.cerias.purdue.edu/~ssw/bell/r1">Factorizations of p^p - 1 for most p < 180</a>
%e A125135 Triangle begins:
%e A125135 3;
%e A125135 2, 13;
%e A125135 2, 2, 11, 71;
%e A125135 2, 3, 29, 4733;
%e A125135 2, 5, 15797, 1806113;
%e A125135 2, 2, 3, 53, 264031, 1803647;
%e A125135 2, 2, 2, 2, 10949, 1749233, 2699538733;
%e A125135 2, 3, 3, 109912203092239643840221;
%e A125135 2, 11, 461, 1289, 831603031789, 1920647391913;
%e A125135 2, 2, 7, 59, 16763, 84449, 2428577, 14111459, 58320973, 549334763;
%e A125135 ...
%e A125135 n=4: p=7, 7^7-1 = 823542 = 2*3*29*4733 gives row 4.
%p A125135 T:= n-> (p-> sort(map(i-> i[1]$i[2], ifactors(p^p-1)[2]))[])(ithprime(n)):
%p A125135 seq(T(n), n=1..10);  # _Alois P. Heinz_, May 20 2022
%o A125135 (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_
%Y A125135 Cf. A006486, A088730, A125136, A212552, A214812.
%K A125135 nonn,tabf
%O A125135 1,1
%A A125135 _N. J. A. Sloane_, Jan 21 2007