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A non-symmetrical rectangular array read by antidiagonals: A(n,m) is the tower of powers of n modulo m.
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%I #19 Aug 25 2020 00:16:54

%S 0,1,0,1,0,0,1,1,1,0,1,0,0,0,0,1,1,3,1,1,0,1,4,2,0,2,0,0,1,2,3,1,1,0,

%T 1,0,1,0,6,4,0,0,1,0,0,1,7,3,4,5,1,3,1,1,0,1,6,0,0,3,0,3,0,0,0,0,1,9,

%U 7,4,5,1,1,1,1,1,1,0,1,4,9,6,2,0,0,4,4,0,2,0,0

%N A non-symmetrical rectangular array read by antidiagonals: A(n,m) is the tower of powers of n modulo m.

%C Although all numbers appear to be present, 1 appears most often followed by 0.

%C Since the first column and main diagonal are equal to 0, all matrices whose upper left corner is on the main diagonal have as their determinant 0.

%D Ilan Vardi, "Computational Recreations in Mathematica," Addison-Wesley Publishing Co., Redwood City, CA, 1991, pages 226-229.

%H Robert G. Wilson v, <a href="/A133612/a133612_2.txt">Mathematica coding for "SuperPowerMod" from Vardi</a>

%e \m 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 ...

%e n\

%e _1 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

%e _2 0 0 1 0 1 4 2 0 7 6 9 4 3 2 1 0

%e _3 0 1 0 3 2 3 6 3 0 7 9 3 1 13 12 11

%e _4 0 0 1 0 1 4 4 0 4 6 4 4 9 4 1 0

%e _5 0 1 2 1 0 5 3 5 2 5 1 5 5 3 5 5

%e _6 0 0 0 0 1 0 1 0 0 6 5 0 1 8 6 0

%e _7 0 1 1 3 3 1 0 7 7 3 2 7 6 7 13 7

%e _8 0 0 1 0 1 4 1 0 1 6 3 4 1 8 1 0

%e _9 0 1 0 1 4 3 1 1 0 9 5 9 1 1 9 9

%e 10 0 0 1 0 0 4 4 0 1 0 1 4 3 4 10 0

%e etc, .

%t (* first load all lines of Super Power Mod by Ilan Vardi from the hyper-link *)

%t Table[ SuperPowerMod[n - m + 1, 2^100, m], {n, 14}, {m, n, 1, -1}] // Flatten (* or *)

%t a[b_, 1] = 0; a[b_, n_] := PowerMod[b, If[OddQ@ b, a[b, EulerPhi[n]], EulerPhi[n] + a[b, EulerPhi[n]]], n]; Table[a[b - m + 1, m], {b, 14}, {m, b, 1, -1}] // Flatten

%Y Cf. A245970, A240162, A245971, A245972, A245973, A245974, A332055, A332054.

%K nonn,tabl

%O 1,18

%A _Jinyuan Wang_ and _Robert G. Wilson v_, Apr 15 2020