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%I #19 Jun 28 2024 13:59:32
%S 0,0,1,1,2,1,0,0,2,1,1,3,4,2,1,2,4,2,4,2,1,1,4,2,1,4,2,1,0,0,0,0,0,4,
%T 2,1,4,2,1,5,7,8,4,2,1,2,6,8,4,2,6,8,4,2,1,1,6,3,7,9,10,5,8,4,2,1,8,4,
%U 8,4,8,4,8,4,8,4,2,1,1,7,10,5,9,11,12,6,3,8,4,2,1,2,8,4,2,8,4,2,8,4,2,8,4,2,1
%N Triangle read by rows: R(n,k) = 2^(n-k) mod n.
%e Triangle begins:
%e 0;
%e 0, 1;
%e 1, 2, 1;
%e 0, 0, 2, 1;
%e 1, 3, 4, 2, 1;
%e 2, 4, 2, 4, 2, 1;
%t Array[PowerMod[2, # - Range[#], #] &, 15] (* _Paolo Xausa_, Jun 28 2024 *)
%o (PARI) row(n) = vector(n, k, lift(Mod(2, n)^(n-k))); \\ _Michel Marcus_, Jun 27 2024
%Y Cf. A000079, A174699.
%Y Cf. A062173 (1st column).
%K nonn,tabl
%O 1,5
%A _Juri-Stepan Gerasimov_, Dec 10 2010
%E Corrected by _D. S. McNeil_, Dec 10 2010