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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, 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
1,3
COMMENTS
It appears that there are no 0's in A112599 after the 6th row. If so, a(p) = p-1 for every prime p except 5 and 7. - Franklin T. Adams-Watters, Nov 15 2006
EXAMPLE
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.
CROSSREFS
Sequence in context: A046522 A242896 A240183 * A158706 A096500 A231563
KEYWORD
nonn
AUTHOR
Leroy Quet, Dec 22 2005
EXTENSIONS
More terms from Franklin T. Adams-Watters, Nov 15 2006
STATUS
approved