%I A123279
%S A123279 1,3,8,105,144,85085,5760,2027025,3203200,4216455243,43545600,
%T A123279 29248404810625,6706022400,1305433904506875,1707444076642304,
%U A123279 191898783962510625,376610217984000,232876694951587194633125
%N A123279 a(n) = product of the first n integers from among those positive integers 
               which are coprime to n.
%H A123279 Leroy Quet, <a href="http://www.prism-of-spirals.net/">Home Page</a> 
               (listed in lieu of email address)
%e A123279 The first 4 positive integers which are coprime to 4 are 1,3,5,7. So 
               a(4) = 1*3*5*7 = 105.
%t A123279 f[n_] := Block[{c = n, k = 0, p = 1},While[c > 0,k++;While[GCD[k, n] 
               > 1, k++ ];c--;p *= k;];p];Table[f[n], {n, 20}] (*Chandler*)
%Y A123279 Cf. A069213, A077581, A077582.
%Y A123279 Sequence in context: A099296 A066619 A028504 this_sequence A134803 A030063 
               A051047
%Y A123279 Adjacent sequences: A123276 A123277 A123278 this_sequence A123280 A123281 
               A123282
%K A123279 nonn
%O A123279 1,2
%A A123279 Leroy Quet Dec 11 2006
%E A123279 Extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Dec 14 2006