OFFSET
1,2
LINKS
Seiichi Manyama, Table of n, a(n) for n = 1..106
B. Mazur, Arithmetic on curves, Bull. Amer. Math. Soc. 14 (1986), 207-259; see p. 225.
FORMULA
P=(0, 0), 2P=(1, 0); if kP = (a, b) then (k+1)P = (a' = (b^2 - a^3)/a^2, b' = -1 - b*a'/a).
a(n) = A028940(2n). - Seiichi Manyama, Nov 19 2016
0 = a(n)*a(n+6) - 5*a(n+1)*a(n+5) + 4*a(n+2)*a(n+4) - 20*a(n+3)^2 for all n in Z. a(n) = A006720(n+1)*A006720(n+2). - Michael Somos, Apr 12 2020
EXAMPLE
4P =(2, -3).
PROG
(PARI) a(n)=numerator(ellmul(E, [0, 0], 2*n)[1]) \\ Charles R Greathouse IV, Mar 23 2022
CROSSREFS
KEYWORD
nonn,frac
AUTHOR
STATUS
approved