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%I #5 Mar 11 2014 01:34:15
%S 1,4,2,9,6,3,16,12,8,5,25,20,15,10,7,36,30,24,18,14,11,49,42,35,28,21,
%T 22,13,64,56,48,40,32,27,26,17,81,72,63,54,45,44,33,34,19,100,90,80,
%U 70,60,50,52,39,38,23,121,110,99,88,77,66,55,68,51,46,29,144,132,120,108
%N Square array read by antidiagonals where the row n lists the numbers k such that their largest divisor <= sqrt(k) equals n.
%C This sequence is a permutation of the natural numbers.
%C Note that the first row is formed by 1 together the prime numbers and the first column are the squares of the natural numbers.
%C For more information see A163280, the main entry for this sequence. (See also A161344).
%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%H Omar E. Pol, <a href="http://www.polprimos.com/imagenespub/poldiv07.jpg">Illustration for A008578, the first row of the array</a> [From _Omar E. Pol_, Oct 24 2009]
%H Omar E. Pol, <a href="http://www.polprimos.com/imagenespub/poldiv08.jpg">Illustration for A161344, the second row of the array</a> [From _Omar E. Pol_, Oct 24 2009]
%H Omar E. Pol, <a href="http://www.polprimos.com/imagenespub/poldiv06.jpg">Illustration for A008578, A161344, A161345 and A161424</a> [From _Omar E. Pol_, Oct 24 2009]
%F Row n lists the numbers k such that A033676(k)=n.
%e Array begins:
%e 1, 2, 3, 5, 7, 11,
%e 4, 6, 8, 10, 14,
%e 9, 12, 15, 18,
%e 16, 20, 24,
%e 25, 30,
%e 36,
%e See also the array in A163280.
%Y Cf. A000027, A000040, A033676, A147861, A163100, A163280, A163281, A163991, A164000.
%Y Cf. Rows: 1=A008578, 2=A161344, 3=A161345, 4=A161424, 5=A161835, 6=A162526, 7=A162527, 8=A162528, 9=A162529, 10=A162530, 11=A162531, 12=A162532.
%Y Cf. Columns: 1=A000290, 2=A002378, 4=A164004, 6=A164006, 7=A164007, 8=A164008, 9=A164009, 10=A164010, 11=A164011, 12=A164012.
%K nonn,tabl
%O 1,2
%A _Omar E. Pol_, Aug 11 2009
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