

A159781


Values of hypotenuse of primitive pythagorean triples which can have four different shapes (that is four different sets of "legs").


3



1105, 1885, 2405, 2465, 2665, 3145, 3445, 3485, 3965, 4505, 4745, 5185, 5365, 5525, 5785, 5945, 6205, 6305, 6409, 6565, 7085, 7345, 7565, 7585, 7685, 8177, 8245, 8585, 8845, 8905, 9061, 9265, 9425, 9605, 9685, 9805, 10205, 10585, 10865
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OFFSET

1,1


COMMENTS

Sequence A024409 lists values of hypotenuse which are common to have more than one shape, and are all actually consisting of two shapes, except 1105 which is the first occurrence of 4 shapes. There are no occurrences of 3 shapes, or more than 4 in the range studied (hypotenuse values 5 to 10,000)
A024362(a(n)) = 4.  Reinhard Zumkeller, Dec 02 2012


LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..100


MATHEMATICA

f[c_] := f[c] = Block[{a = 1, b, cnt = 0, lmt = Floor[Sqrt[c^2/2]]}, While[b = Sqrt[c^2  a^2]; a < lmt, If[IntegerQ@ b && GCD[a, b, c] == 1, cnt++]; a++]; cnt]Select[1 + 4 Range[2800], f@# > 2 &] (* Robert G. Wilson v, Mar 16 2014 *)


PROG

(Haskell)
import Data.List (elemIndices)
a159781 n = a159781_list !! (n1)
a159781_list = map (+ 1) $ elemIndices 4 a024362_list
 Reinhard Zumkeller, Dec 02 2012


CROSSREFS

Cf. A024409 and A146945
Cf. A006278 (8, 16 etc. shapes). [From R. J. Mathar, Apr 12 2010]
Sequence in context: A052155 A097102 A281877 * A264498 A102924 A214017
Adjacent sequences: A159778 A159779 A159780 * A159782 A159783 A159784


KEYWORD

nonn


AUTHOR

John T. Harrison (harrison_uk_2000(AT)yahoo.co.uk), Apr 22 2009


EXTENSIONS

6429 replaced by 6409 and 3 terms added by R. J. Mathar, Apr 12 2010
Missing 8585 and 8845 inserted by Reinhard Zumkeller, Dec 02 2012


STATUS

approved



