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A173948 a(n) = denominator of 8 Catalan + Pi^2 - Zeta[2, (4 n + 1)/4] 11
1, 1, 25, 2025, 342225, 98903025, 4846248225, 121156205625, 101892368930625, 12328976640605625, 16878369020989100625, 28372538324282678150625, 28372538324282678150625, 1390254377889851229380625, 3905224547492592103330175625, 1409786061644825749302193400625, 5245813935380396613153461643725625 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

For n>=2 numbers in this sequence are divisible by 25.

For n>=7 numbers in this sequence are divisible by 25^2.

LINKS

Table of n, a(n) for n=0..16.

MATHEMATICA

Table[Denominator[RootApproximant[N[8 Catalan + \[Pi]^2 - Zeta[2, (4 k + 1)/4], 100], 1]], {k, 0, 20}]

CROSSREFS

Cf. A120268, A173945, A173947.

Sequence in context: A197671 A051112 A061843 * A197408 A197430 A195272

Adjacent sequences:  A173945 A173946 A173947 * A173949 A173950 A173951

KEYWORD

frac,nonn

AUTHOR

Artur Jasinski, Mar 03 2010

STATUS

approved

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Last modified December 22 16:00 EST 2014. Contains 252364 sequences.