1,1

127 = 2^7 - 1 is a Mersenne prime and its "look and say" description, 111217, is also prime, so 127 belongs to the sequence.

Cf. A005150.

Sequence in context: A042329 A125956 A128071 this_sequence A005844 A156521 A012636

Adjacent sequences: A079619 A079620 A079621 this_sequence A079623 A079624 A079625

base,nonn

Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Jan 30 2003