1,2
AGM is the arithmetic-geometric mean.
Table of n, a(n) for n=1..120.
Eric Weisstein's World of Mathematics, Arithmetic-Geometric Mean
1.918724665977634529660378250749815...
RealDigits[ ArithmeticGeometricMean[1, Pi], 10, 120] // First (* Jean-François Alcover, Mar 07 2013 *)
(PARI) agm(1, Pi)
Cf. A191220
Sequence in context: A234468 A011111 A301815 * A109871 A087500 A238168
Adjacent sequences: A191499 A191500 A191501 * A191503 A191504 A191505
nonn,cons
Franklin T. Adams-Watters, Jun 03 2011
approved