Triangular numbers composed of digits {0,1,2}.

Terms

a(0) =1a(1) =10a(2) =21a(3) =120a(4) =210a(5) =2211a(6) =10011a(7) =20100a(8) =112101a(9) =222111a(10) =2001000a(11) =22221111a(12) =110120220a(13) =122000010a(14) =200010000a(15) =1210000221a(16) =2222211111a(17) =12001110201a(18) =20000100000a(19) =122021211021a(20) =222222111111