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A085267 Numbers having at least two representations as sum of a squarefree number and a nonzero square. 2
6, 7, 10, 11, 12, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 26, 27, 28, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers n such that A085263(a(n)) > 1.

Conjecture: for n > 50, a(n) = n + 11. - Charles R Greathouse IV, Oct 26 2011

LINKS

Table of n, a(n) for n=1..67.

Eric Weisstein's World of Mathematics, Square Number

Eric Weisstein's World of Mathematics, Squarefree

PROG

(PARI) is(n)=my(t); forstep(k=sqrtint(n-1), 1, -1, if(issquarefree(n-k^2), if(t++>1, return(1)))); 0 \\ Charles R Greathouse IV, Mar 12 2012

CROSSREFS

Cf. A085265, A085266.

Sequence in context: A006364 A037301 A163247 * A118957 A037303 A135121

Adjacent sequences:  A085264 A085265 A085266 * A085268 A085269 A085270

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jun 23 2003

STATUS

approved

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Last modified December 6 06:34 EST 2019. Contains 329784 sequences. (Running on oeis4.)