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A174885 Prime hypotenuses c with concatenation p = c//a//b a prime number. 0
29, 409, 461, 661, 929, 1249, 1289, 1381, 1801, 1901, 2081, 2609, 2621, 2749, 3041, 3301, 3881, 5309, 5701, 6421, 6481, 6521, 6529, 7349, 7489, 7789, 8641, 8849, 9349, 9629, 9649, 9689, 9829, 10321, 10709, 10861, 12841, 14321, 14561, 15061, 16661 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
See comments in A174825
c is the prime hypotenuse c, i. e. c of a primitive Pythagorean triple: a^2 + b^2 = c^2
REFERENCES
W. W. R. Ball, H. S. M. Coxeter: Mathematical Recreations and Essays, New York: Dover, 1987
L. E. Dickson: "Rational Right Triangles", ch. 4 in History of the Theory of numbers, vol. II, Dover Publications 2005
W. Sierpinski: Pythagorean Triangles, Mineola, NY, Dover Publications, Inc, 2003
LINKS
EXAMPLE
p = c//a//b: 292021, 409120391, 461380261, 661300589, 929920129, 1249960799, 12895601161,
13811020931, 18011680649, 19011820549, 208116401281, 260918801809, 262111002379,
27492580949, 30414403009, 330129401501, 388123603081, 53095300309, 570122205251
29^2=20^2+21^2, 409^2=120^2+391^2, 461^2=380^2+261^2,
661^2=300^2+589^2, 929^2=920^2+129^2, 1249^2=960^2+799^2,
1289^2=560^2+1161^2,1381^2=1020^2+931^2, 1801^2=1680^2+649^2,
1901^2=1820^2+549^2, 2081^2=1640^2+1281^2, 2609^2=1880^2+1809^2,
2621^2=1100^2+2379^2, 2749^2=2580^2+949^2, 3041^2=440^2+3009^2,
3301^2=2940^2+1501^2, 3881^2=2360^2+3081^2, 5309^2=5300^2+309^2,
5701^2=2220^2+5251^2
CROSSREFS
Sequence in context: A010945 A022624 A042630 * A264160 A210302 A163021
KEYWORD
base,nonn,uned
AUTHOR
Ulrich Krug (leuchtfeuer37(AT)gmx.de), Apr 01 2010
EXTENSIONS
More terms from Zak Seidov, Apr 04 2010
STATUS
approved

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Last modified April 24 19:39 EDT 2024. Contains 371963 sequences. (Running on oeis4.)