The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A243497 A243496 sorted into ascending order, with duplicates removed. 4

%I #13 Jul 29 2014 13:46:46

%S 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,

%T 103,121,125,127,128,131,169,227,241,243,256,277,289,311,331,343,361,

%U 419,431,509,512,529,563,661,691,709,719,739,841,961,1009,1024,1433,1523,1619,1681,1787,1849,1879,2063

%N A243496 sorted into ascending order, with duplicates removed.

%C 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).

%C 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.

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

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

%K nonn

%O 0,2

%A _Antti Karttunen_, Jun 07 2014

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 3 08:59 EDT 2024. Contains 373057 sequences. (Running on oeis4.)