%I #6 Jun 18 2021 07:22:44

%S 1,1,2,11,12,31,1111,15,51,121,1211,11212,114111,2111213,21313111,

%T 13111111113,111114181,118151111,5111131114,2111414131,1413113111111,

%U 131111111111216,1111217110111,13101114111213,4111214111313111

%N Concatenation of the numbers of equal successive digits of previous two terms, starting with a(1)=a(2)=1.

%e As a(6)=1111 and a(7)=15, their digits are 111115, that is (5) 1's followed by (1) 1, so a(8) = 51.

%Y Cf. A113721.

%K nonn,base

%O 1,3

%A _Floor van Lamoen_, Nov 08 2005

%E Definition adapted to offset by _Georg Fischer_, Jun 18 2021