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>polygamma9</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 <mfenced> 15 <mrow> 16 <mi>n</mi> 17 </mrow> 18 </mfenced> 19 </msup> 20 <mfenced> 21 <mrow> 22 <mfrac> 23 <mn>1</mn> 24 <mn>2</mn> 25 </mfrac> 26 </mrow> 27 </mfenced> 28 <mo>=</mo> 29 <msup> 30 <mfenced> 31 <mrow> 32 <mo>−</mo> 33 <mn>1</mn> 34 </mrow> 35 </mfenced> 36 <mrow> 37 <mi>n</mi> 38 <mo>+</mo> 39 <mn>1</mn> 40 </mrow> 41 </msup> 42 <mi>n</mi> 43 <mo>!</mo> 44 <mfenced> 45 <mrow> 46 <msup> 47 <mn>2</mn> 48 <mrow> 49 <mi>n</mi> 50 <mo>+</mo> 51 <mn>1</mn> 52 </mrow> 53 </msup> 54 <mo>−</mo> 55 <mn>1</mn> 56 </mrow> 57 </mfenced> 58 <mi>ς</mi> 59 <mfenced> 60 <mrow> 61 <mi>n</mi> 62 <mo>+</mo> 63 <mn>1</mn> 64 </mrow> 65 </mfenced> 66 </mrow> 67</math> 68</body> 69</html>