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%I #13 Nov 14 2016 10:37:18
%S 0,0,0,0,3,0,4,0,6,5,8,0,9,0,12,14,15,0,10,0,16,20,18,0,22,7,21,26,27,
%T 0,24,0,30,25,28,33,34,0,36,38,32,0,40,0,35,44,42,0,39,11,48,45,50,0,
%U 46,51,54,55,49,0,57,0,60,62,52,58,56,0,63,68,66,0,70,0,64,74,69,65,75,0,76,80,78,0,81,84,82,86,72,0,87,77,85,13,92,91,88,0
%N a(n) = the largest k < n for which A277892(k) = A277892(n), 0 if no such number exists, a(0) = a(1) = 0.
%H Antti Karttunen, <a href="/A277894/b277894.txt">Table of n, a(n) for n = 0..10000</a> (computed from the 10000 term b-file provided by _Hans Havermann_ for A277892)
%F For n >= 3, a(A277893(n)) = n.
%o (Scheme) (define (A277894 n) (cond ((<= n 2) 0) (else (let ((v (A277892 n))) (let loop ((k (- n 1))) (cond ((= 1 k) 0) ((= (A277892 k) v) k) (else (loop (- k 1)))))))))
%Y Cf. A277892, A277893, A277895.
%Y Cf. A008578 (gives the positions of zeros after a(0)).
%K nonn
%O 0,5
%A _Antti Karttunen_, Nov 08 2016