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%I #4 Dec 05 2013 19:56:18
%S 3,2,0,19,35,13,343,0,39,43,275,103,55,14,0,67,539,37,99,62,21,137,
%T 2375,49,51,4913,279,173,2639,61,0,65,33,34,0,73,265,38,999,163,1595,
%U 257,175,44,91,281,29375,0,99,203,207,211,2375,219,783,341,57,353,14399,487,123
%N Smallest number a(n) == -1 (mod n) such that the prime signature of n and a(n) is the same, or 0 if no such number exists.
%e a(6) =35 = 6*6 -1 = 3*13 and 6 = 2*3 are both of prime signature p*q, where p and q are primes.
%Y Cf. A085074.
%K nonn
%O 2,1
%A _Amarnath Murthy_, Jul 01 2003
%E More terms from _David Wasserman_, Jan 12 2005