A268916 - OEIS

%I #5 Feb 20 2016 21:05:51

%S 12,12,6,12,12,4,24,6,24,3,60,60,60,60,12,12,6,4,6,12,2,84,84,84,84,

%T 84,84,12,48,12,48,3,48,12,48,3,36,36,4,36,36,4,36,36,4,60,30,60,30,

%U 12,30,60,30,60,6,132,132,132,132,132,132,132,132,132,132,12,24,6,8,3,24,2,24,3,8,6,24,1

%N Denominators of the rational number triangle R(m, a) = -(m^2 - 6*m*a + a^2)/(12*m), m >= 1, a = 1, ..., m.

%C For the numerators see A268915.

%C For details and the Hurwitz reference see A267863.

%F T(m, a) = denominator(R(m, a)) with R(m, a) = -(m^2 - 6*m*a + a^2)/(12*m), m >= 1, a = 1, ..., m.

%e The triangle T(m, a) begins:

%e m\a   1   2   3   4   5   6   7   8   9  10  11

%e 1:   12

%e 2:   12   6

%e 3:   12  12   4

%e 4:   24   6  24   3

%e 5:   60  60  60  60  12

%e 6:   12   6   4   6  12   2

%e 7:   84  84  84  84  84  84  12

%e 8:   48  12  48   3  48  12  48   3

%e 9:   36  36   4  36  36   4  36  36   4

%e 10:  60  30  60  30  12  30  60  30  60   6

%e 11: 132 132 132 132 132 132 132 132 132 132 12

%e 12:  24   6   8   3  24   2  24   3   8   6  24  1

%e ...

%e For the triangle of the rationals R(m, a) see A268915.

%Y Cf. A268915.

%K nonn,frac,tabl,easy

%O 1,1

%A _Wolfdieter Lang_, Feb 18 2016