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A181744
Numbers n such that x(x+n)=y*y has one and only one positive integer solution (x,y).
0
3, 5, 6, 7, 8, 10, 11, 12, 13, 14, 17, 19, 20, 22, 23, 26, 28, 29, 31, 34, 37, 38, 41, 43, 44, 46, 47, 52, 53, 58, 59, 61, 62, 67, 68, 71, 73, 74, 76, 79, 82, 83, 86, 89, 92, 94, 97, 101, 103, 106, 107, 109, 113, 116, 118, 122, 124, 127, 131, 134, 137, 139, 142, 146, 148
OFFSET
1,1
COMMENTS
The sequence contains all primes and their doubles and quadruples (except 2 and 4).
EXAMPLE
118 belongs to the sequence since 1682*(1682+118)=1682*1800=1740^2
CROSSREFS
Sequence in context: A114978 A138891 A163162 * A343217 A160685 A080218
KEYWORD
nonn
AUTHOR
Carmine Suriano, Nov 08 2010
EXTENSIONS
Name corrected by Robert Israel, Mar 04 2016
STATUS
approved