id:A020886 - OEIS Search Results

Search: id:A020886

Displaying 1-1 of 1 results found.

page 1

A020886

Ordered semiperimeters of primitive Pythagorean triangles.

+0
28

6, 15, 20, 28, 35, 42, 45, 63, 66, 72, 77, 88, 91, 99, 104, 110, 117, 120, 130, 143, 153, 156, 165, 170, 187, 190, 195, 204, 209, 210, 221, 228, 231, 238, 247, 255, 266, 272, 273, 276, 285, 299, 304, 322, 323, 325, 336, 342, 345, 350, 357, 368, 378, 391, 399 (list; graph; listen)

	OFFSET	`0,1`
	COMMENT	`n is in this sequence iff A078926(n)>0. This is a subset of A005279.`
	MAPLE	`isA020886 := proc(an) local r::integer, s::integer ; for r from floor((an/2)^(1/2)) to floor(an^(1/2)) do for s from r-1 to 1 by -2 do if r(r+s) = an and gcd(r, s) < 2 then RETURN(true) ; fi ; if r(r+s) < an then break ; fi ; od ; od : RETURN(false) ; end : for n from 2 to 400 do if isA020886(n) then printf("%d, ", n) ; fi ; od ; - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jun 08 2006`
	CROSSREFS	`Cf. A020882-A020885. a(n) = A024364(n)/2.` `Sequence in context: A045848 A044439 A128253 this_sequence A093508 A094183 A162693` `Adjacent sequences: A020883 A020884 A020885 this_sequence A020887 A020888 A020889`
	KEYWORD	`nonn`
	AUTHOR	`Clark Kimberling (ck6(AT)evansville.edu)`

page 1

Search completed in 0.002 seconds

Last modified November 25 08:46 EST 2009. Contains 167481 sequences.

AT&T Labs Research