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A316563
Maximum order of an element in the special linear group SL(2, Z(n)).
5
1, 3, 6, 6, 10, 12, 14, 8, 18, 30, 22, 12, 26, 42, 30, 16, 34, 18, 38, 30, 42, 66, 46, 24, 50, 78, 54, 42, 58, 60, 62, 32, 66, 102, 70, 36, 74, 114, 78, 40, 82, 84, 86, 66, 90, 138, 94, 48, 98, 150, 102, 78, 106, 54, 110, 56, 114, 174, 118, 60, 122, 186, 126
OFFSET
1,2
LINKS
PROG
(GAP) Concatenation([1], List([2..15], n->Maximum(List(SL(2, Integers mod n), Order))));
(PARI)
MatOrder(M)={my(id=matid(#M), k=1, N=M); while(N<>id, k++; N=N*M); k}
a(n)={my(m=0); for(a=0, n-1, for(b=0, n-1, for(c=0, n-1, for(d=0, n-1, my(M=Mod([a, b; c, d], n)); if(matdet(M)==1, m=max(m, MatOrder(M))))))); m}
CROSSREFS
Row lengths of A316564.
Sequence in context: A184161 A276000 A333616 * A349212 A316140 A147849
KEYWORD
nonn
AUTHOR
Andrew Howroyd, Jul 06 2018
STATUS
approved