|
Search: id:A057229
|
|
|
| A057229 |
|
a(n) = a*b = x*y with (a-b) = (x+y) = A020882(n) (a>b, a>0, b>0, x>0, y>0), gcd(a, b) = gcd(x, y) = 1. |
|
+0
2
|
|
| 6, 30, 60, 84, 210, 210, 180, 630, 330, 504, 924, 1320, 546, 1386, 1560, 2340, 990, 2730, 840, 2574, 4620, 1224, 1716, 3570, 5610, 7140, 4290, 1710, 5016, 7956, 7980, 2730, 7854, 10374, 2310, 11970, 6630, 10920, 12540, 4080, 3036, 11856, 8970
(list; graph; listen)
|
|
|
OFFSET
|
0,1
|
|
|
COMMENT
|
The quadratics in X, X^2 - S*X -+ P, where S=A020882(n), P=A057229(n) are each factorizable into two factors, all four being distinct: X^2 - S*X - P = (X - a)*(X + b). X^2 - S*X + P = (X - x)*(X - y). - Lekraj Beedassy (blekraj(AT)yahoo.com), Apr 30 2004
Areas of primitive Pythagorean triangles sorted on hypotenuse A020882, then on perimeter A093507. - Lekraj Beedassy (blekraj(AT)yahoo.com), Aug 18 2006
|
|
LINKS
|
P. Yiu, Factorizable x^2 + px -+ q, Recreational Mathematics, pp. 58, Vol. 360.
|
|
EXAMPLE
|
E.g. a(1)=6=6*1=3*2, (6-1)=(3+2)=5=A020882(1), gcd(6,1)=gcd(3,2)=1
|
|
CROSSREFS
|
Cf. A020882, A008846, A024406, A024365.
Sequence in context: A044083 A024406 A024365 this_sequence A120734 A116360 A065800
Adjacent sequences: A057226 A057227 A057228 this_sequence A057230 A057231 A057232
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Naohiro Nomoto (6284968128(AT)geocities.co.jp), Sep 19 2000
|
|
|
Search completed in 0.002 seconds
|
