A080138 Least positive integer multiples of angle x such that their direction cosines form a unit vector: sum(k>0, cos(a(k)*x)^2)=1, where a(1)=1 and x=3.

1, 11, 12, 33, 100, 122, 144, 233, 344, 477, 588, 832, 943, 1187, 2008, 15853, 16563, 17273, 121621, 191068, 260515, 503757, 573204, 955340, 1337476, 1719612, 2101748, 3317603, 4464011, 4846147, 5228283, 5610419, 10647634, 16066985

Offset

1,2

Links

Table of n, a(n) for n=1..34.

Prog

(PARI) x=3; z=cos(x)^2; a=1; for(n=1, 35, b=a+1; while(z+cos(b*x)^2>1, b++); z=z+cos(b*x)^2; a=b; print1(b, ", "))

Crossrefs

Cf. A080136, A080137, A080139, A080140.

Sequence in context: A061760 A309631 A075559 * A244068 A041252 A041250

Adjacent sequences: A080135 A080136 A080137 * A080139 A080140 A080141

Keyword

nonn

Author

Paul D. Hanna, Jan 30 2003

Extensions

Corrected and extended with PARI program by Benoit Cloitre, Feb 04 2003

Status

approved