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%I #14 Mar 22 2017 14:52:41
%S 1,3,6,10,13,23,27,30,34,38,48,54,62,65,69,86,90,94,103,120,127,131,
%T 135,139,144,148,161,165,185,197,211,255,258,262,275,286,290,300,311,
%U 319,330,334,350,354,358,367,375,379,399,414,420,427,443,447,453,457,465,486,500,504,530,534,549,555,559
%N Numbers k such that gcd(A280864(k), A280864(k+1)) = 1.
%H N. J. A. Sloane, <a href="/A280774/b280774.txt">Table of n, a(n) for n = 1..25317</a>
%Y Cf. A280864.
%Y First differences give A283832.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Jan 19 2017