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A260437 Column index to A255543: if n is Lucky number then a(n) = 0, otherwise a(n) = the position at the stage where n is removed in the Lucky sieve.

%I A260437 #8 Aug 02 2015 17:53:31
%S A260437 0,1,0,2,1,3,0,4,0,5,2,6,0,7,0,8,3,9,1,10,0,11,4,12,0,13,1,14,5,15,0,
%T A260437 16,0,17,6,18,0,19,2,20,7,21,0,22,1,23,8,24,0,25,0,26,9,27,1,28,2,29,
%U A260437 10,30,3,31,0,32,11,33,0,34,0,35,12,36,0,37,0,38,13,39,0,40,4,41,14,42,1,43,0,44,15,45,3,46,0,47,16,48,2,49,0,50,17,51,5,52
%N A260437 Column index to A255543: if n is Lucky number then a(n) = 0, otherwise a(n) = the position at the stage where n is removed in the Lucky sieve.
%H A260437 Antti Karttunen, <a href="/A260437/b260437.txt">Table of n, a(n) for n = 1..10003</a>
%F A260437 Other identities. For all n >= 1:
%F A260437 a(n) = A260429(n) - 1.
%F A260437 Iff A145649(n) = 1, then a(n) = 0.
%F A260437 a(2n) = n.
%F A260437 a(A219178(n)) = 1.
%F A260437 A255543(A260438(A050505(n)), a(A050505(n))) = A050505(n).
%o A260437 (Scheme) (define (A260437 n) (cond ((not (zero? (A145649 n))) 0) ((even? n) (/ n 2)) (else (let searchrow ((row 2)) (let searchcol ((col 1)) (cond ((>= (A255543bi row col) n) (if (= (A255543bi row col) n) col (searchrow (+ 1 row)))) (else (searchcol (+ 1 col))))))))) ;; Code for A255543bi given in A255543.
%Y A260437 One less than A260429.
%Y A260437 Cf. A000959, A050505, A145649, A219178, A255543.
%Y A260437 Cf. also A260438 (corresponding row index).
%K A260437 nonn
%O A260437 1,4
%A A260437 _Antti Karttunen_, Aug 02 2015