%I A118809
%S A118809 1,2,3,5,6,9,4,10,11,13,8,16,12,14,17,20,15,22,7,25,21,24,18,31,26,28,
%T A118809 27,33,19,36,29,35,34,37,38,44,30,40,39,47,23,48,32,49,46,45,42,57,50,
%U A118809 54,51,55,41,61,56,63,58,59,52,70,53,62,67,68,64,72,60,73,66,77,43,83
%N A118809 a(1) = 1. a(n) = (number of earlier terms which divide n)th positive
integer not occurring among the earlier terms of the sequence.
%C A118809 Likely a permutation of the positive integers.
%H A118809 Leroy Quet, <a href="http://www.prism-of-spirals.net/">Home Page</a>
(listed in lieu of email address)
%e A118809 The first 7 terms of the sequence are 1,2,3,5,6,9,4. Of these there are
3 terms (1, 2 and 4) that divide 8, so we want for a(8) the 3rd positive
integer not among the first 7 terms of the sequence (i.e. we want
the third term of 7,8,10,11,...). So a(8)= 10.
%p A118809 A118809 := proc(nmin) local a,anxt,i,n,j ; a := [1] ; while nops(a) <
nmin do n := nops(a)+1 ; i := 0 ; for j in a do if n mod j = 0 then
i := i+1 ; fi ; od: anxt := 0 ; while i > 0 do anxt := anxt+1 ; while
anxt in a do anxt := anxt+1 ; od ; i := i-1; od ; a := [op(a),anxt]
; od; a ; end: A118809(100) ; - R. J. Mathar (mathar(AT)strw.leidenuniv.nl),
Sep 06 2007
%Y A118809 Cf. A118810.
%Y A118809 Sequence in context: A128994 A098211 A073673 this_sequence A121048 A075389
A053784
%Y A118809 Adjacent sequences: A118806 A118807 A118808 this_sequence A118810 A118811
A118812
%K A118809 nonn
%O A118809 1,2
%A A118809 Leroy Quet Apr 30 2006
%E A118809 More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Sep 06 2007
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