A112631 Rightmost term of each row of triangle A112599. (For n >= 2, a(n) = number of terms in the (n-1)th row of triangle A112599 which are coprime to n.)
1, 1, 2, 0, 2, 0, 3, 5, 7, 5, 10, 4, 12, 9, 6, 5, 16, 3, 18, 2, 17, 5, 22, 8, 22, 12, 13, 8, 28, 5, 30, 5, 30, 15, 22, 9, 36, 23, 18, 16, 40, 2, 42, 15, 20, 9, 46, 20, 46, 12, 23, 21, 52, 10, 33, 26, 40, 27, 58, 21, 60, 23, 41, 31, 55, 11, 66, 32, 44, 21, 70, 19, 72, 23, 40, 28, 63, 17
Offset: 1
Keywords
Examples
The 6th row of triangle A112599 is [5,0,4,0,4,0]. So a(7) is the number of these terms which are coprime to 7. Now 5, 4 and 4 are coprime to 7, but the 0's are not; so a(7) = 3.
Extensions
More terms from Franklin T. Adams-Watters, Nov 15 2006
Comments