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1,2
Sequence with a(1) = 2 is decimal expansion of sqrt(4 + sqrt(4 + sqrt(4 + sqrt(4 + ... )))) - A222132.
Table of n, a(n) for n=1..105.
Closed form: (sqrt(17) - 1)/2 = A178255-2 = A082486-3 = A222132-1.
sqrt(4 - sqrt(4 - sqrt(4 - sqrt(4 - ... )))) + 1 = sqrt(4 + sqrt(4 + sqrt(4 + sqrt(4 + ... )))). See A222132.
1.561552812808830274910704...
RealDigits[(Sqrt[17] - 1)/2, 10, 130]
Cf. A178255, A082486, A222132.
Sequence in context: A080130 A188640 A198419 * A198728 A238135 A195449
Adjacent sequences: A222130 A222131 A222132 * A222134 A222135 A222136
nonn,cons
Jaroslav Krizek, Feb 08 2013
approved