|
| |
|
|
A046143
|
|
Triangle of GCD( 2^p-1, 2^q-1 ) = 2^GCD(p,q) - 1.
|
|
0
| |
|
|
1, 1, 3, 1, 1, 7, 1, 3, 1, 15, 1, 1, 1, 1, 31, 1, 3, 7, 3, 1, 63, 1, 1, 1, 1, 1, 1, 127, 1, 3, 1, 15, 1, 3, 1, 255, 1, 1, 7, 1, 1, 7, 1, 1, 511, 1, 3, 1, 3, 31, 3, 1, 3, 1, 1023, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2047, 1, 3, 7, 15, 1, 63, 1, 15, 7, 3, 1, 4095, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
(list; table; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,3
|
|
|
COMMENTS
| The function T(n,k) = T(k,n) is defined for k>n but only the values for 1<=k<=n as a triangular array are listed here.
|
|
|
LINKS
| Eric Weisstein's World of Mathematics, More information
|
|
|
EXAMPLE
| Triangle begins
{1},
{1,3},
{1,1,7},
{1,3,1,15},
{1,1,1,1,31},
{1,3,7,3,1,63},
|
|
|
MATHEMATICA
| T[ n_, k_] := If[ n < 1 || k < 1, 0, 2^GCD[ n, k] - 1] (* Michael Somos Jul 18 2011 *)
|
|
|
PROG
| {T(n, k) = if( n<1 || k<1, 0, 2^gcd(n, k) - 1)} /* Michael Somos Jul 18 2011 */
|
|
|
CROSSREFS
| Sequence in context: A102479 A053193 A010273 * A071812 A116407 A135288
Adjacent sequences: A046140 A046141 A046142 * A046144 A046145 A046146
|
|
|
KEYWORD
| nonn,tabl
|
|
|
AUTHOR
| Eric Weisstein (eric(AT)weisstein.com)
|
| |
|
|
