1,6
Below 64 the following six composite connected numbers occur: 15,45,51,55,57,63, so a(6)=6.
Cf. A029827, A007053 and A029837, A036378-A036390.
Sequence in context: A142875 A074981 A066510 this_sequence A053560 A119874 A134259
Adjacent sequences: A036384 A036385 A036386 this_sequence A036388 A036389 A036390
nonn
Labos E. (labos(AT)ana.sote.hu)
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