Ljunggren also posed the question of finding the integer solutions to the Ramanujan–Nagell equation
Schrödinger equation | Nernst equation | Monge–Ampère equation | Boltzmann equation | Diophantine equation | Ramanujan | Ordinary differential equation | ordinary differential equation | Young–Laplace equation | Wave equation | wave equation | Vlasov equation | Tait equation | Smoluchowski coagulation equation | Sauerbrey equation | SASTRA Ramanujan Prize | Redlich–Kwong equation of state | Ramanujan tau function | Ramanujan Prize | Ramanujan–Nagell equation | Quadratic equation | Prony equation | Pell's equation | Mathieu's equation | Marchenko equation | Majorana's equation | Linear equation | linear equation | Liénard equation | Kepler's equation |
Lubotzky, Phillips, and Sarnak (1988), Margulis (1988), and Morgenstern (1994) show how Ramanujan graphs can be constructed explicitly.
He first proposed in a letter to G. H. Hardy dated 28 July 1920 to pay Ramanujan's wife a monthly annuity of 20 rupees per month for handing over her husband's documents.
From December 15, 2005 to December 16, 2005, the sessions were named after famous mathematicians such as Andrey Markov, G H Hardy and Ramanujan.
This was proved by his Ph.D. student Karl Mahlburg in his 2005 paper Partition Congruences and the Andrews–Garvan–Dyson Crank, linked below.
Ramanujan tau function, giving the Fourier coefficients of the Ramanujan modular form.