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%I #28 Aug 12 2022 09:24:02
%S 2,6,2,2,12,2,30,2,24,2,2,60,2,24,2,42,2,120,2,24,2,2,252,2,240,2,24,
%T 2,30,2,504,2,240,2,24,2,2,60,2,504,2,240,2,24,2,66,2,120,2,504,2,240,
%U 2,24,2,2,132,2,240,2,504,2,240,2,24,2
%N Triangle read by rows: T(n,k) = gcd {x^n - x^k : x is an integer}, 0 < k < n.
%C All diagonals are weakly increasing, T(n,k) divides T(n+1,k+1), and the m-th diagonal converges to A079612(m).
%C First column is A027760.
%C First value where T(n,k) < gcd(2^n - 2^k, 3^n - 3^k) is T(12,1) = 2 < 46.
%C Maximum value in the n-th row is given by A330542(n).
%H Peter Kagey, <a href="/A330541/b330541.txt">Table of n, a(n) for n = 2..10012</a> (first 141 rows, flattened)
%H Mathematics Stack Exchange, <a href="https://math.stackexchange.com/q/3474696/121988">Computing gcd {n^k - n^l : n in Z}</a>.
%e Table begins:
%e n\k| 1 2 3 4 5 6 7 8 9 10 11
%e ---+-------------------------------------------------
%e 2 | 2;
%e 3 | 6, 2;
%e 4 | 2, 12, 2;
%e 5 | 30, 2, 24, 2;
%e 6 | 2, 60, 2, 24, 2;
%e 7 | 42, 2, 120, 2, 24, 2;
%e 8 | 2, 252, 2, 240, 2, 24, 2;
%e 9 | 30, 2, 504, 2, 240, 2, 24, 2;
%e 10 | 2, 60, 2, 504, 2, 240, 2, 24, 2;
%e 11 | 66, 2, 120, 2, 504, 2, 240, 2, 24, 2;
%e 12 | 2, 132, 2, 240, 2, 504, 2, 240, 2, 24, 2.
%Y Cf. A027760, A079612, A330542.
%K nonn,tabl
%O 2,1
%A _Peter Kagey_, Dec 17 2019
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