A138900 - OEIS

%I #6 Mar 30 2012 17:35:01

%S 1,9,18,38,98,384,2580,2580,2580,2580,2580,367574,721449,3879720,

%T 3879720,53671968,53671968,223610114

%N First gap of length at least n in A136110, lower end.

%e First few terms of A136110 are 1,3,4,6,7,9,12,13,15,17,18,22,23,... . The first gap of length 1 is between 1 and 3, hence a(1) = 1; the first gap of length 2 is between 9 and 12, hence a(2) = 9; the first gap of length 3 is between 18 and 22, hence a(3) = 18. The first gap of length at least 7 is between 2580 and 2592; it has length 11,

%e hence a(7) = a(8) = a(9) = a(10) = a(11) = 2580.

%Y Cf. A136110, A138899, A138845.

%K nonn,more

%O 1,2

%A _Klaus Brockhaus_, Apr 03 2008

%E a(14)-a(18) from _Donovan Johnson_, Nov 27 2010