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A277893(n) = the least k > n for which A277892(k) = A277892(n), 0 if no such number exists.
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%I #13 Nov 14 2016 10:37:05

%S 0,4,6,9,8,25,10,12,18,49,14,93,15,16,20,169,22,287,21,26,24,361,30,

%T 33,27,28,34,529,32,802,40,35,36,44,38,934,39,48,42,1333,46,1681,45,

%U 51,54,1754,50,58,52,55,64,2209,56,57,66,60,65,2809,62,2966,63,68,74,77,70

%N A277893(n) = the least k > n for which A277892(k) = A277892(n), 0 if no such number exists.

%C a(n) is the least k larger than n for which the number of divisors of A048675(k) is equal to the number of divisors of A048675(n) (counted with multiplicity), and 0 if no such number exists (which happens only for n=2).

%H Antti Karttunen, <a href="/A277893/b277893.txt">Table of n, a(n) for n = 2..102</a> (computed from the b-file provided by Hans Havermann for A277892)

%F For n >= 3, A277894(a(n)) = n.

%o (Scheme) (define (A277893 n) (cond ((= 2 n) 0) (else (let ((v (A277892 n))) (let loop ((k (+ 1 n))) (if (= (A277892 k) v) k (loop (+ 1 k))))))))

%Y Cf. A048675, A277892, A277894, A277898.

%K nonn

%O 2,2

%A _Antti Karttunen_, Nov 08 2016