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A201911
Irregular triangle of 7^k mod prime(n).
8
1, 1, 1, 2, 4, 3, 0, 1, 7, 5, 2, 3, 10, 4, 6, 9, 8, 1, 7, 10, 5, 9, 11, 12, 6, 3, 8, 4, 2, 1, 7, 15, 3, 4, 11, 9, 12, 16, 10, 2, 14, 13, 6, 8, 5, 1, 7, 11, 1, 7, 3, 21, 9, 17, 4, 5, 12, 15, 13, 22, 16, 20, 2, 14, 6, 19, 18, 11, 8, 10, 1, 7, 20, 24, 23, 16, 25
OFFSET
1,4
COMMENTS
Except for the fourth row, the first term of each row is 1. Many sequences are in this one: starting at A036132 (mod 71) and A070404 (mod 11).
LINKS
EXAMPLE
The first 9 rows are:
1
1
1, 2, 4, 3
0
1, 7, 5, 2, 3, 10, 4, 6, 9, 8
1, 7, 10, 5, 9, 11, 12, 6, 3, 8, 4, 2
1, 7, 15, 3, 4, 11, 9, 12, 16, 10, 2, 14, 13, 6, 8, 5
1, 7, 11
1, 7, 3, 21, 9, 17, 4, 5, 12, 15, 13, 22, 16, 20, 2, 14, 6, 19, 18, 11, 8, 10
MATHEMATICA
nn = 10; p = 7; 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(7, P[n]));;
Flat(Concatenation([1, 1, 1, 2, 4, 3, 0], List([5..10], n->List([0..R[n]-1], k->PowerMod(7, k, P[n]))))); # Muniru A Asiru, Feb 01 2019
CROSSREFS
Cf. A201908 (2^k), A201909 (3^k), A201910 (5^k).
Cf. A070404 (11), A070405 (13), A070407 (17), A070409 (23), A070413 (29), A070415 (31), A070420 (37), A070422 (39), A070424 (41), A070425 (43), A070429 (47), A036132 (71).
Sequence in context: A351427 A381410 A391482 * A048644 A246713 A106137
KEYWORD
nonn,tabf
AUTHOR
T. D. Noe, Dec 07 2011
STATUS
approved