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%I #6 Feb 06 2015 02:49:14
%S 1,2,3,6,4,5,10,15,9,21,28,7,8,14,36,45,20,55,66,13,27,78,91,35,105,
%T 120,11,12,19,44,136,153,54,171,190,26,65,210,231,77,253,276,18,34,90,
%U 300,325,104,351,378,43,119,406,435,135,465,496,16,17,25,53,152,528,561,170,595,630,64,189,666,703,209,741,780,33,76
%N Inverse permutation to A254105.
%H Antti Karttunen, <a href="/A254106/b254106.txt">Table of n, a(n) for n = 1..8192</a>
%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%o (Scheme) (define (A254106 n) (let ((col (A254112 n)) (row (A254111 n))) (* (/ 1 2) (- (expt (+ col row) 2) col row row row -2))))
%Y Inverse: A254105.
%Y Cf. A254108, A254111, A254112.
%K nonn
%O 1,2
%A _Antti Karttunen_, Jan 27 2015