cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A097754 Table read by antidiagonals of least integer "mod 4 prime signatures" k ordered by number of primitive Pythagorean triples with hypotenuse = k.

Original entry on oeis.org

1, 2, 5, 3, 25, 65, 4, 125, 325, 1105, 6, 625, 1625, 5525, 32045, 8, 3125, 4225, 27625, 160225, 1185665, 9, 15625, 8125, 71825, 801125, 5928325, 48612265, 10, 78125, 21125, 138125, 2082925, 29641625, 243061325, 2576450045, 12, 390625, 40625
Offset: 1

Views

Author

Ray Chandler, Aug 26 2004

Keywords

Comments

See A097751 for definition of "mod 4 prime signature".
Row 0 of table represents "mod 4 prime signature" values k such that no PPTs have hypotenuse=k.
Row n of table, n>0, represents "mod 4 prime signature" values k such that 2^(n-1) PPTs have hypotenuse=k.

Examples

			Table begins:
0: 1,2,3,4,6,8,9,10,12,15,16,18,20,21,24,27,30,...
1: 5,25,125,625,3125,15625,78125,390625,1953125,...
2: 65,325,1625,4225,8125,21125,40625,105625,203125,...
4: 1105,5525,27625,71825,138125,359125,690625,1221025,...
8: 32045,160225,801125,2082925,4005625,10414625,20028125,...
16: 1185665,5928325,29641625,77068225,148208125,385341125,...
32: 48612265,243061325,1215306625,3159797225,6076533125,...
64: 2576450045,12882250225,64411251125,167469252925,...
128: 157163452745,785817263725,3929086318625,10215624428425,...
256: 11472932050385,57364660251925,286823301259625,...
		

Crossrefs

Row 1 is A000351 except for starting point.

Extensions

Correct offset. Ray Chandler, Jan 15 2013