A267102 - OEIS

%I #6 Jan 17 2016 20:25:45

%S 1,2,3,4,6,10,5,7,15,21,28,9,36,14,8,11,45,55,66,78,20,91,105,27,120,

%T 35,13,136,44,19,12,16,153,171,190,210,231,54,253,276,300,65,325,351,

%U 77,378,90,26,406,435,104,465,119,34,496,135,43,18,528,152,53,25,17,22,561,595,630,666,703,741,170,780,820

%N Inverse permutation to A265901.

%H Antti Karttunen, <a href="/A267102/b267102.txt">Table of n, a(n) for n = 1..10000</a>

%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>

%F a(n) = (1/2) * ((c+r)^2 - r - 3*c + 2), where c = A265332(n), and r = A162598(n).

%o (Scheme) (define (A267102 n) (let ((col (A265332 n)) (row (A162598 n))) (* (/ 1 2) (- (expt (+ row col) 2) row col col col -2))))

%Y Inverse: A265901.

%Y Cf. A162598, A265332.

%K nonn

%O 1,2

%A _Antti Karttunen_, Jan 10 2016