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A201910
Irregular triangle of 5^k mod prime(n).
7
1, 1, 2, 0, 1, 5, 4, 6, 2, 3, 1, 5, 3, 4, 9, 1, 5, 12, 8, 1, 5, 8, 6, 13, 14, 2, 10, 16, 12, 9, 11, 4, 3, 15, 7, 1, 5, 6, 11, 17, 9, 7, 16, 4, 1, 5, 2, 10, 4, 20, 8, 17, 16, 11, 9, 22, 18, 21, 13, 19, 3, 15, 6, 7, 12, 14, 1, 5, 25, 9, 16, 22, 23, 28, 24, 4
OFFSET
1,3
COMMENTS
Except for the third row, the first term of each row is 1. Many sequences are in this one: starting at A036121 (mod 23) and A070365 (mod 7).
LINKS
EXAMPLE
The first 9 rows are:
1
1, 2
0
1, 5, 4, 6, 2, 3
1, 5, 3, 4, 9
1, 5, 12, 8
1, 5, 8, 6, 13, 14, 2, 10, 16, 12, 9, 11, 4, 3, 15, 7
1, 5, 6, 11, 17, 9, 7, 16, 4
1, 5, 2, 10, 4, 20, 8, 17, 16, 11, 9, 22, 18, 21, 13, 19, 3, 15, 6, 7, 12, 14
MATHEMATICA
nn = 10; p = 5; t = p^Range[0, Prime[nn]]; Flatten[Table[If[Mod[n, p] == 0, {0}, tm = Mod[t, n]; len = Position[tm, 1, 1, 2][[-1, 1]]; Take[tm, len-1]], {n, Prime[Range[nn]]}]]
PROG
(GAP) P:=Filtered([1..350], IsPrime);;
R:=List([1..Length(P)], n->OrderMod(5, P[n]));;
Flat(Concatenation([1, 1, 2, 0], List([3..10], n->List([0..R[n]-1], k->PowerMod(5, k, P[n]))))); # Muniru A Asiru, Feb 02 2019
CROSSREFS
Cf. A201908 (2^k), A201909 (3^k), A201911 (7^k).
Cf. A070365 (7), A070367 (11), A070368 (13), A070371 (17), A070373 (19), A036121 (23), A070379 (29), A070384 (37), A070387 (41), A070389 (43), A036127 (47), A036133 (73), A036137 (97), A036139 (103), A036149 (157), A036151 (167), A036156 (193).
Sequence in context: A197808 A085650 A343751 * A109450 A086810 A085838
KEYWORD
nonn,tabf
AUTHOR
T. D. Noe, Dec 07 2011
STATUS
approved