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A243118 Numbers n such that A242962(x) = n has no solution. 3

%I #4 May 30 2014 01:04:38

%S 2,4,5,7,9,10,11,16,17,19,21,22,23,25,26,27,29,33,34,35,37,41,43,45,

%T 46,47,49,50,51,52,53,55,58,59,61,64,65,66,67,69,70,71,73,75,76,77,79,

%U 81,82,83,85,86,87,88,89,92,94,95,97,99,100,101,103,105,106

%N Numbers n such that A242962(x) = n has no solution.

%C A242962(n) = (n*(n+1)/2) mod antisigma(n) = A000217(n) mod A024816(n); where A000217(n) = triangular numbers, A024816(n) = sum of numbers less than n which do not divide n.

%C Union of A007369 and numbers 4 and 7.

%C Complement of A243117.

%C a(n) = A007369(n-2) for n >= 5, where A007369 = numbers n such that sigma(x) = n has no solution.

%e 4 is in the sequence because there is no x whose A242962(x) = 4.

%Y Cf. A000203, A007369, A242962, A242963, A243117.

%K nonn

%O 1,1

%A _Jaroslav Krizek_, May 29 2014

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