A368325 Union of primorials and powers of 2.

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

1,2

Comments

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

Links

Michael De Vlieger, Table of n, a(n) for n = 1..3671

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.

Mathematica

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

Crossrefs

Cf. A000079, A000961, A002110, A005117, A025487, A055932, A126706, A303554, A363814, A364710.

Sequence in context: A317306 A317087 A100778 * A324579 A271520 A122408

Adjacent sequences: A368322 A368323 A368324 * A368326 A368327 A368328

Keyword

nonn,easy

Author

Michael De Vlieger, Jan 30 2024

Status

approved