1,1

First few terms of A007951 are 1,2,4,5,7,8,10,11,14,16, ... . The first gap of length 1 is between 2 and 4, so a(1) = 2; the first gap of length 2 is between 11 and 14, so a(2) = 11.

Cf. A007951, A138845, A138900, A139386.

Sequence in context: A104087 A154596 A066382 this_sequence A041725 A077544 A087480

Adjacent sequences: A139384 A139385 A139386 this_sequence A139388 A139389 A139390

nonn,more

Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Apr 17 2008