1<?xml version='1.0'?> 2<!DOCTYPE html PUBLIC '-//W3C//DTD XHTML 1.1 plus MathML 2.0//EN' 3 'http://www.w3.org/TR/MathML2/dtd/xhtml-math11-f.dtd' 4 [<!ENTITY mathml 'http://www.w3.org/1998/Math/MathML'>]> 5<html xmlns='http://www.w3.org/1999/xhtml'> 6<head><title>polygamma2</title> 7<!-- MathML created with MathCast Equation Editor version 0.89 --> 8</head> 9<body> 10<math xmlns="http://www.w3.org/1998/Math/MathML" display="block"> 11 <mrow> 12 <msup> 13 <mi>ψ</mi> 14 <mrow> 15 <mfenced> 16 <mrow> 17 <mi>n</mi> 18 </mrow> 19 </mfenced> 20 </mrow> 21 </msup> 22 <mfenced> 23 <mrow> 24 <mn>1</mn> 25 <mo>−</mo> 26 <mi>x</mi> 27 </mrow> 28 </mfenced> 29 <mo>=</mo> 30 <msup> 31 <mfenced> 32 <mrow> 33 <mo>−</mo> 34 <mn>1</mn> 35 </mrow> 36 </mfenced> 37 <mi>n</mi> 38 </msup> 39 <msup> 40 <mi>ψ</mi> 41 <mrow> 42 <mfenced> 43 <mrow> 44 <mi>n</mi> 45 </mrow> 46 </mfenced> 47 </mrow> 48 </msup> 49 <mfenced> 50 <mrow> 51 <mi>x</mi> 52 </mrow> 53 </mfenced> 54 <mo>+</mo> 55 <msup> 56 <mfenced> 57 <mrow> 58 <mo>−</mo> 59 <mn>1</mn> 60 </mrow> 61 </mfenced> 62 <mi>n</mi> 63 </msup> 64 <mi>π</mi> 65 <mfrac> 66 <mrow> 67 <msup> 68 <mo>∂</mo> 69 <mi>n</mi> 70 </msup> 71 <mi>cot</mi> 72 <mfenced> 73 <mrow> 74 <mi>π</mi> 75 <mi>x</mi> 76 </mrow> 77 </mfenced> 78 </mrow> 79 <mrow> 80 <mo>∂</mo> 81 <msup> 82 <mi>x</mi> 83 <mi>n</mi> 84 </msup> 85 </mrow> 86 </mfrac> 87 </mrow> 88</math> 89</body> 90</html>