%I A119584
%S A119584 0,0,2,3,20,5,70,53,121,87,330,117,572,305,507,553,1360,481,1938,873,
%T A119584 1586,1405,3542,1241,3846,2415,4006,2765,7308,1875,8990,4945,6828,5675,
%U A119584 9333,4525,15540,8053,11567,7745,21320,6047,24682,12005,15244,14625
%N A119584 Sum{k=1 to phi(n)-1} t(n,k)*t(n,k+1), where t(n,k) is the k-th positive
integer which is coprime to n and phi(n) is the number of positive
integers which are <= n and are coprime to n.
%C A119584 All primes are records and there exists records which are not primes,
but they are rare (see A120033). - Robert G. Wilson v (rgwv(at)rgwv.com),
Jun 05 2006
%H A119584 Leroy Quet, <a href="http://www.prism-of-spirals.net/">Home Page</a>
(listed in lieu of email address)
%e A119584 The positive integers which are <= 8 and are coprime to 8 are 1, 3, 5
and 7. So a(8) = 1*3 + 3*5 + 5*7 = 53.
%t A119584 f[n_] := Block[{s = Select[ Range@n, GCD[ #, n] == 1 &]}, Plus @@ (Most@s*Rest@s)];
Array[f, 46] - Robert G. Wilson v (rgwv(at)rgwv.com), Jun 05 2006
%Y A119584 Sequence in context: A038584 A108022 A108884 this_sequence A089181 A028425
A024630
%Y A119584 Adjacent sequences: A119581 A119582 A119583 this_sequence A119585 A119586
A119587
%K A119584 nonn
%O A119584 1,3
%A A119584 Leroy Quet May 31 2006
%E A119584 More terms from Robert G. Wilson v (rgwv(at)rgwv.com), Jun 05 2006
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