Research keywords (10)：
Mean value
, Mellin-Barnes integral formula
, analytic continuation
, confluent hypergeometric function
, Functional equation
, Dirichlet L-function
, Mordell-Tornheim multiple zeta function
, the zeta-function of the root system
, multiple zeta value
, multiple zeta function
Research theme for competitive and other funds (3)：
2015 - 2019 様々な多重ゼータ関数と超幾何関数の関係とその応用
2012 - 2014 ルート系のゼータ関数の値に関係する解析的性質の研究
2010 - 2012 多重ゼータ関数の解析的性質と、その代数的応用についての研究
Papers (12)：
Shin-ya Kadota, Takuya Okamoto, Masataka Ono, Koji Tasaka. On a unified double zeta function of Mordell-Tornheim type. Lithuanian Mathematical Journal. 2022. 62. 2. 207-217
S. Kadota, T. Okamoto, K. Tasaka. Evaluation of Torheim’s type of double series. Illinois Journal of Math. 2017. 61. 1-2. 171-186
Takuya Okamoto, Tomokazu Onozuka. Functional equation for the mordell-tornheim multiple zeta-function. Functiones et Approximatio, Commentarii Mathematici. 2016. 55. 2. 227-241
門田慎也, 岡本卓也, 田坂浩二. On the special values of the zeta function associated with simple Lie algebra type G_2. 数理解析研究所講究録. 2018. 2092. 1-8
岡本卓也, 小野塚友一. The mean values of Dirichlet L-functions. 数理解析研究所講究録. 2017. 2014. 155-160
Okamoto Takuya, Onozuka Tomokazu. Functional equation for the Mordell-Tornheim multiple zeta-function (解析的整数論 : 数論的対象の分布と近似). 数理解析研究所講究録. 2016. 2013. 178-183
Okamoto Takuya, Onozuka Tomokazu. Mean values of Mordell-Tornheim double zeta-functions (Analytic Number Theory : Arithmetic Properties of Transcendental Functions and their Applications). RIMS Kokyuroku. 2014. 1898. 70-79
Okamoto Takuya. Analytic properties of a certain multiple Dirichlet series (Analytic number theory and related topics). RIMS Kokyuroku. 2010. 1710. 53-59
Lectures and oral presentations (16)：
A relation between the multiple zeta-function and the hypergeometric function and its application
(2019)
On the special values of the zeta function associated with simple Lie algebra type G_2
(Analytic Number Theory and Related Areas 2017)
Multiple zeta values of the root system of type A_3
(Seminar on analytic number theory 2017)
Values of zeta-functions of root systems of type G_2 at integer points
(Seminar on analytic number theory 2016)
