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.

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A370409 Numbers k = m * s, where s is composite and squarefree, rad(m) divides s, and 1 < m <= s, where rad() = A007947().

Original entry on oeis.org

12, 18, 20, 24, 28, 36, 40, 44, 45, 50, 52, 56, 60, 63, 68, 75, 76, 80, 84, 88, 90, 92, 98, 99, 100, 104, 112, 116, 117, 120, 124, 126, 132, 135, 136, 140, 147, 148, 150, 152, 153, 156, 164, 168, 171, 172, 175, 176, 180, 184, 188, 189, 196, 198, 204, 207, 208
Offset: 1

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Author

Michael De Vlieger, Feb 22 2024

Keywords

Comments

A177492 is a proper subset.
Proper subset of A126706.

Examples

			Let T(j,k) = row j of A162306 and let s = A120944(n), n > 1.
This sequence contains finite sequences R(s) = s * T(s, 2..A010846(s)). The cardinality of R(s) is A010846(s)-1.
For s = 6, this sequence contains {12, 18, 24, 36},
  i.e., A033845(2..A010846(6)).
For s = 10, this sequence contains {20, 40, 50, 80, 100},
  i.e., A033846(2..A010846(10)).
For s = 14, this sequence contains {28, 56, 98, 112, 196},
  i.e., A033847(2..A010846(14)).
For s = 15, this sequence contains {45, 75, 135, 225},
  i.e., A033849(2..A010846(15)), etc.
		

Crossrefs

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