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A183422 Ordering of the numbers in the tree A183420; complement of A183423. 3
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..87.

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.

EXAMPLE

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.

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

CROSSREFS

Cf. A183423, the complement of A183422.

Sequence in context: A128716 A258934 A225600 * A025057 A189753 A278450

Adjacent sequences:  A183419 A183420 A183421 * A183423 A183424 A183425

KEYWORD

nonn

AUTHOR

Clark Kimberling, Jan 04 2011

STATUS

approved

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Last modified June 20 09:27 EDT 2019. Contains 324234 sequences. (Running on oeis4.)