A183422 Ordering of the numbers in the tree A183420; complement of A183423.
2, 4, 6, 9, 12, 14, 16, 18, 20, 22, 25, 27, 30, 32, 34, 36, 38, 40, 42, 44, 46, 49, 51, 53, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 81, 83, 85, 87, 90, 92, 94, 96, 100, 102, 104, 106, 110, 112, 114, 116, 119, 121, 123, 125, 127, 130, 132, 134, 136, 138, 141, 144, 146, 148, 150, 153, 156, 158, 160, 162, 165, 169, 171, 173, 175, 178, 182, 184, 186, 188, 191, 194, 196, 198, 200
Offset: 1
Keywords
Examples
The complementary trees A183420 and A183421 contain initial terms (2,14,4,254,18,34,6,...) and (1,7,3,79,10,23,5,...). A183422 comes from arranging in increasing order the numbers in the first tree: (2,4,6,9,,12,14,...), these being complementary to the numbers in the second tree.
Programs
-
Mathematica
nn=200; t={2}; t0=t; While[t=Select[Union[t,(t^2+4t+2),t+Floor[1/2+(t+2)^(1/2)]], #<=nn&]; t0 !=t, t0=t]; t
Formula
The monotonic ordering of the numbers in the set S generated by these rules: 2 is in S, and if n is in S, then n^2+4*n+2 and n+Floor[1/2+sqrt(n+2)] is in S.