A243497 A243496 sorted into ascending order, with duplicates removed.

1, 2, 3, 4, 5, 7, 8, 9, 11, 16, 17, 19, 23, 25, 27, 31, 32, 49, 53, 59, 64, 67, 81, 83, 97, 103, 121, 125, 127, 128, 131, 169, 227, 241, 243, 256, 277, 289, 311, 331, 343, 361, 419, 431, 509, 512, 529, 563, 661, 691, 709, 719, 739, 841, 961, 1009, 1024, 1433, 1523, 1619, 1681, 1787, 1849, 1879, 2063

Offset

0,2

Comments

Matula-codes for trees which are almost "uniform", but which allow cases like 169, 841, 1009, 1681, 1849, ... where there is a special relation between prime index and the exponent. (Cf. the comments at A243496).

Differs from A214577 for the first time at n=31, where A214577(31)=227, while here we have 169 at that position, because it corresponds exactly to that "dual" case mentioned in A057546, in excess to those mentioned in A003238. Note that 169 = 13*13 = p_{2*3}^2.

a(0) = 1 stands for the empty tree.

Links

Table of n, a(n) for n=0..64.

Crossrefs

Cf. A214577 (a subsequence), A209638, A243494.

Sequence in context: A318612 A318690 A302498 * A214577 A280994 A138039

Adjacent sequences: A243494 A243495 A243496 * A243498 A243499 A243500

Keyword

nonn

Author

Antti Karttunen, Jun 07 2014

Status

approved