

A233421


Let m = nth nonsquare = A000037(n); then a(n) = A006255(m).


2



6, 8, 10, 12, 14, 15, 18, 22, 20, 26, 21, 24, 34, 27, 38, 30, 28, 33, 46, 32, 39, 35, 40, 58, 42, 62, 45, 44, 51, 48, 74, 57, 52, 50, 82, 56, 86, 55, 60, 69, 94, 54, 63, 68, 65, 106, 70, 66, 72, 76, 87, 118, 75, 122, 93, 77, 78, 80, 134, 85, 92, 84
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OFFSET

1,1


LINKS

Peter Kagey, Table of n, a(n) for n = 1..5000
AoPS Forum, 2013 Putnam Contest, Problem A2, Dec 08 2013
R. L. Graham, Bijection between integers and composites, Problem 1242, Math. Mag., 60 (1987), p. 180. [Note that unless you subscribe to JSTOR this link will only show page 178, which contains a different problem proposed by R. L. Graham.  N. J. A. Sloane, Jan 13 2014]


FORMULA

a(n) = A006255(A000037(n)).  Michel Marcus, Jan 07 2014


EXAMPLE

a(1) = A006255(A000037(1)) = A006255(2) = 6 because 2*3*6 = 6^2.
a(2) = A006255(A000037(2)) = A006255(3) = 8 because 3*6*8 = 12^2.


CROSSREFS

Arguments are numbers that are nonsquares: A000037.
This is A006255 with perfect squares omitted.
Sequence in context: A000379 A176525 A065985 * A060652 A020739 A064466
Adjacent sequences: A233418 A233419 A233420 * A233422 A233423 A233424


KEYWORD

nonn


AUTHOR

Peter Kagey, Dec 09 2013


EXTENSIONS

Edited by Michel Marcus and N. J. A. Sloane, Jan 13 2014


STATUS

approved



