A087642 Sequence of squarefree n such that Q(sqrt(n)) has no element with a fully periodical continued fraction of period 1.

3, 6, 7, 11, 14, 15, 19, 21, 22, 23, 30, 31, 33, 34, 35, 38, 39, 42, 43, 46, 47, 51, 55, 57, 59, 62, 66, 67, 69, 70, 71, 77, 78, 79, 83, 86, 87, 91, 93, 94, 95, 102, 103, 105, 107, 110, 111, 114, 115, 118, 119, 123, 127, 129, 131, 133, 134, 138, 139, 141, 142, 143, 146

Offset: 3

Author

Thomas Baruchel, Sep 16 2003

Keywords

• easy
• nonn

Comments

Diophantine equation x^2 - n.y^2 + 4 = 0 has no solution (x,y) for a given squarefree n. Squarefree n not in the sequence A013946. Same sequence with square factors allowed is A087643.

Examples

			3 is in the sequence because no [k,k,k,k,...] is in Q(sqrt(3))
5 is not in the sequence since Q(sqrt(5)) contains [1,1,1,1,...]
		

Crossrefs

Cf. A087643, A013946.