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Discovered independently by Niels Henrik Abel (1823) and Giovanni Antonio Amedeo Plana (1820).
Etymology from Wiktionary, CC BY-SA 4.0.
Abel-Plana formula
Today it means: A summation formula stating that ∑ₙ₌₀ ᪲f(a+n)=∫ₐ ᪲f(x)dx+(f(a))/2+∫₀ ᪲(f(a-ix)-f(a+ix))/(i(e^(2πx)-1))dx. Full definition →