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a(n) = rightmost term of n-th row of triangle A112592. (For n >= 2, a(n) = number of terms in the (n-1)th row of triangle A112592 which are coprime to n.)
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%I #12 May 11 2014 22:39:59

%S 0,0,1,2,4,0,3,5,4,1,10,0,6,2,13,10,16,1,18,6,14,8,22,4,23,6,17,8,28,

%T 15,30,11,19,18,24,2,36,21,28,12,40,12,42,20,24,21,46,12,47,24,36,2,

%U 40,21,49,37,22,26,58,14,60,31,51,44,50,8,66,36,44,23,70,8,72,37,55,40,62,20

%N a(n) = rightmost term of n-th row of triangle A112592. (For n >= 2, a(n) = number of terms in the (n-1)th row of triangle A112592 which are coprime to n.)

%H Diana Mecum, <a href="/A112635/b112635.txt">Table of n, a(n) for n = 1..517</a> [From _Diana L. Mecum_, Aug 12 2008]

%e The 6th row of triangle A112592 is [5,0,5,0,5,0]. So a(7) is the number of these terms which are coprime to 7. Now the three 5's are coprime to 7, but the 0's are not; so a(7) = 3.

%Y Cf. A112592, A112631.

%K nonn

%O 1,4

%A _Leroy Quet_, Dec 27 2005

%E Terms a(10) through a(517) from _Diana L. Mecum_, Aug 12 2008