dlmf.nist.gov

• equiv: content-type content: text/html; charset=UTF-8
• name: viewport content: width=device-width, initial-scale=1

• http://dlmf.nist.gov/./
• Index
• Notations
• Help?
• Citing
• Customize
• About the Project
• http://dlmf.nist.gov/about/news/#S1.I1.i1
• http://dlmf.nist.gov/about/news/#S1.I1.i2
• http://dlmf.nist.gov/about/news/#S1.I1.i3
• http://dlmf.nist.gov/about/news/#S1.I1.i4
• More news
• http://dlmf.nist.gov/./front/foreword
• http://dlmf.nist.gov/./front/preface
• http://dlmf.nist.gov/./front/introduction
• http://dlmf.nist.gov/./1
• http://dlmf.nist.gov/./2
• http://dlmf.nist.gov/./3
• http://dlmf.nist.gov/./4
• http://dlmf.nist.gov/./5
• http://dlmf.nist.gov/./6
• http://dlmf.nist.gov/./7
• http://dlmf.nist.gov/./8
• http://dlmf.nist.gov/./9
• http://dlmf.nist.gov/./10
• http://dlmf.nist.gov/./11
• http://dlmf.nist.gov/./12
• http://dlmf.nist.gov/./13
• http://dlmf.nist.gov/./14
• http://dlmf.nist.gov/./15
• http://dlmf.nist.gov/./16
• http://dlmf.nist.gov/./17
• http://dlmf.nist.gov/./18
• http://dlmf.nist.gov/./19
• http://dlmf.nist.gov/./20
• http://dlmf.nist.gov/./21
• http://dlmf.nist.gov/./22
• http://dlmf.nist.gov/./23
• http://dlmf.nist.gov/./24
• http://dlmf.nist.gov/./25
• http://dlmf.nist.gov/./26
• http://dlmf.nist.gov/./27
• http://dlmf.nist.gov/./28
• http://dlmf.nist.gov/./29
• http://dlmf.nist.gov/./30
• http://dlmf.nist.gov/./31
• http://dlmf.nist.gov/./32
• http://dlmf.nist.gov/./33
• http://dlmf.nist.gov/./34
• http://dlmf.nist.gov/./35
• http://dlmf.nist.gov/./36
• Bibliography
• List of Figures
• List of Tables
• Software
• Errata
• © 2010–2025 NIST
• Disclaimer
• Feedback
• Help

• NIST Handbook of Mathematical Functions
• http://www.nist.gov/
• Site Privacy
• Accessibility
• Privacy Program
• Copyrights
• Vulnerability Disclosure
• No Fear Act Policy
• FOIA
• Environmental Policy
• Scientific Integrity
• Information Quality Standards
• Commerce.gov
• Science.gov
• USA.gov

            Domain Name: NIST.GOV
Registrar: get.gov
Domain Status: server transfer prohibited
Creation Date: 1997-10-02T01:29:27.000Z
Registry Expiry Date: 2027-08-24T23:36:29.109Z
Updated Date: 2026-07-05T15:04:09.675Z
Name Server: GOLD.FOUNDATIONDNS.COM
Name Server: GOLD.FOUNDATIONDNS.NET
Name Server: GOLD.FOUNDATIONDNS.ORG
REGISTRAR Contact: get.gov
ADMINISTRATIVE Contact: REDACTED FOR PRIVACY
SECURITY Contact: REDACTED FOR PRIVACY
TECHNICAL Contact: REDACTED FOR PRIVACY
>>> Last update of RDAP database: 2026-07-17T03:24:39Z         

			# robots.txt, presumably for all virtual sites

# PetalBot is dumb and creates millions of hits per week on dlmf.
User-agent: PetalBot
Disallow: /

User-agent: *
Disallow: /cgi-bin/
Disallow: /~SRessler/x3dom/x3domCaesar/

# https://www.semrush.com/bot/
# block SemrushBot a webgraph of links:
User-agent: SemrushBot
Disallow: /
# block SemrushBot different SEO and technical issues:
User-agent: SiteAuditBot
Disallow: /
# block SemrushBot Backlink Audit tool:
User-agent: SemrushBot-BA
Disallow: /
# block SemrushBot On Page SEO Checker tool and similar tools:
User-agent: SemrushBot-SI
Disallow: /
# block SemrushBot from checking URLs on your site for SWA tool:
User-agent: SemrushBot-SWA
Disallow: /
# block SemrushBot Content Analyzer and Post Tracking tools:
User-agent: SemrushBot-CT
Disallow: /
# block SemrushBot Brand Monitoring:
User-agent: SemrushBot-BM
Disallow: /
# block SplitSignalBot SplitSignal tool:
User-agent: SplitSignalBot
Disallow: /
# block SemrushBot-COUB Content Outline Builder tool:
User-agent: SemrushBot-COUB
Disallow: /


# 2023-01-17  https://mj12bot.com/
User-agent: MJ12bot
Disallow: /

# 2023-01-17 https://naver.me/spd
User-agent: Yeti
Disallow: /

# 2023-01-17 https://zhanzhang.toutiao.com/
User-agent: Bytespider
Disallow: /

# 2023-01-17 http://www.eyemon.it/
User-agent: EyeMonIT
Disallow: /

# commented per ping by bruce 2023-05-11 since they're sending annoying email to lots of people at nist. :-)
# # 2023-01-17 http://www.bing.com/bingbot.htm
# User-agent: bingbot
# Disallow: /
# User-agent: Bingbot
# Disallow: /

# 2023-01-17 http://yandex.com/bots
User-agent: YandexBot
Disallow: /
User-agent: Yandex
Disallow: /

# 2023-01-17 https://opensiteexplorer.org/dotbot
User-agent: DotBot
Disallow: /
User-agent: dotbot
Disallow: /

# 2023-01-17 http://ahrefs.com/robot/
User-agent: AhrefsBot
Disallow: /

# 2023-01-17 https://help.mail.ru/webmaster/indexing/robots
User-agent: Mail.Ru
Disallow: /

# 2023-01-17 http://help.coccoc.com/searchengine
User-agent: coccocbot-web
Disallow: /
User-agent: coccocbot
Disallow: /

# 2023-01-30 http://megaindex.com/crawler
User-agent: MegaIndex
Disallow: /

        

SEO tecnica

SEO sulla pagina

Contenuti e UX