A094173 - OEIS

A094173

a(n) = m if m has already occurred at least once and n=k+i*(m+1) where k is the index of the first occurrence of n and i=1,...,max(n-1,1), otherwise a(n) = least positive integer that has not yet occurred.

%I #11 Apr 03 2014 00:11:45

%S 1,2,1,3,2,4,5,3,6,7,4,3,5,8,9

%N a(n) = m if m has already occurred at least once and n=k+i*(m+1) where k is the index of the first occurrence of n and i=1,...,max(n-1,1), otherwise a(n) = least positive integer that has not yet occurred.

%C Is the sequence possible for all n?

%C a(16) does not exist: it would have to be 4 (since a(6) = a(11) = 4 and so a(6 + 2*(4 + 1)) = a(16) = 4) and also 6 (since a(9) = 6 and so a(9 + 1*(6 + 1)) = a(16) = 6) simultaneously. - Herman Jamke (hermanjamke(AT)fastmail.fm), May 01 2008

%Y Cf. A095162, A095163, A095164.

%K nonn,fini,full

%O 1,2

%A _Amarnath Murthy_, Jun 01 2004

%E Edited by Herman Jamke (hermanjamke(AT)fastmail.fm), May 01 2008