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A076043
a(1)=2; for n>1, a(n) is smallest squarefree number (greater than 1) not occurring earlier such that a(n) + a(n-1) is a square.
0
2, 7, 29, 35, 14, 11, 5, 31, 33, 3, 6, 10, 15, 21, 43, 38, 26, 23, 13, 51, 30, 19, 17, 47, 34, 66, 55, 89, 107, 37, 159, 97, 227, 62, 59, 22, 42, 39, 61, 83, 86, 58, 111, 85, 239, 122, 74, 70, 155, 41, 103, 93, 163, 161, 95, 101, 223, 138, 87, 57, 139, 185, 71, 73, 123, 46
OFFSET
0,1
COMMENTS
Conjecture: every squarefree number except 1 is a member.
CROSSREFS
Sequence in context: A122118 A337429 A059803 * A180448 A116968 A162172
KEYWORD
nonn,easy
AUTHOR
Amarnath Murthy, Nov 03 2002
EXTENSIONS
Corrected and extended by Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 20 2003
STATUS
approved