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A177887
The areas of Pythagorean triangles divided by 6.
0
1, 4, 5, 9, 10, 14, 16, 20, 25, 30, 35, 36, 40, 45, 49, 55, 56, 64, 80, 81, 84, 90, 91, 100, 105, 120, 121, 125, 126, 140, 144, 154, 160, 165, 169, 180, 196, 204, 220, 224, 225, 231, 245, 250, 256, 260, 270, 285, 286, 289, 315, 320, 324, 336, 350, 360, 361, 364, 385, 390
OFFSET
1,2
COMMENTS
Number of terms less than 10^k: 4, 23, 109, 462, 1861, 7255, 27042, 95703, 314534, ..., .
This is A009112/6. - T. D. Noe, Oct 08 2013
Same as A256418/24, i.e., congrua/24. - Jonathan Sondow, Nov 07 2017
REFERENCES
Albert H. Beiler, Recreations in the Theory of Numbers, The Queen of Mathematics Entertains, 2nd Ed., Chpt. XIV, "The Eternal Triangle", pp. 104-134, Dover Publ., NY, 1964.
FORMULA
A009112(n)/6.
MATHEMATICA
(* First run the program given for A009112 *) Union[t/6]
CROSSREFS
Sequence in context: A001983 A143575 A047208 * A032381 A191888 A050036
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Dec 14 2010
STATUS
approved