1,1
a(1)=5 because there are 5 central binomial coefficients with 1 digit : 1,1,2,3,6,
Cf. A001405.
Sequence in context: A019102 A019179 A147533 this_sequence A134206 A134209 A019842
Adjacent sequences: A137237 A137238 A137239 this_sequence A137241 A137242 A137243
easy,nonn
Ctibor O. ZIZKA (ctibor.zizka(AT)seznam.cz), Mar 09 2008
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