cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-1 of 1 results.

A368325 Union of primorials and powers of 2.

Original entry on oeis.org

1, 2, 4, 6, 8, 16, 30, 32, 64, 128, 210, 256, 512, 1024, 2048, 2310, 4096, 8192, 16384, 30030, 32768, 65536, 131072, 262144, 510510, 524288, 1048576, 2097152, 4194304, 8388608, 9699690, 16777216, 33554432, 67108864, 134217728, 223092870, 268435456, 536870912, 1073741824
Offset: 1

Views

Author

Michael De Vlieger, Jan 30 2024

Keywords

Comments

Numbers that (1) are either prime powers or squarefree and (2) have a primorial kernel.

Crossrefs

Programs

  • Mathematica
    Union@ Flatten@ {#, 2^Range[Log2[Last[#] ] ] } &@
      FoldList[Times, 1, Prime@ Range[nn]]

Formula

Union of A000079 and A002110.
Intersection of A055932 and A303554.
Intersection of A025487 and A303554.
{a(n)} = A055932 \ A126706 = A025487 \ A126706.
A055932 = union of this sequence and A363814.
A025487 = union of this sequence and A364710.
Showing 1-1 of 1 results.