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.

A239626 Factored over the Gaussian integers, n has a(n) prime factors counted multiply, including units -1, i, and -i.

Original entry on oeis.org

1, 3, 1, 5, 3, 4, 1, 7, 2, 5, 1, 6, 3, 4, 4, 8, 3, 5, 1, 7, 2, 4, 1, 8, 5, 5, 3, 6, 3, 6, 1, 11, 2, 5, 4, 7, 3, 4, 4, 8, 3, 5, 1, 6, 5, 4, 1, 9, 2, 7, 4, 7, 3, 6, 4, 8, 2, 5, 1, 8, 3, 4, 3, 13, 5, 5, 1, 7, 2, 6, 1, 9, 3, 5, 6, 6, 2, 6, 1, 11, 4, 5, 1, 7, 5, 4, 4
Offset: 1

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Author

T. D. Noe, Mar 31 2014

Keywords

Comments

Here -1, i, and -i are counted as factors. The factor 1 is counted only in a(1).

Examples

			a(2) = 3 because 2 = -i * (1 + i)^2.
a(3) = 1 because 3 is prime over the complex numbers.
a(4) = 5 because 4 = -1 * (1 + i)^4.
		

Crossrefs

Cf. A001221, A001222 (integer factorizations).
Cf. A078458, A086275 (Gaussian factorizations).
Cf. A239627 (Gaussian factorization including units).

Programs

  • Mathematica
    Table[Total[Transpose[FactorInteger[n, GaussianIntegers -> True]][[2]]], {n, 100}]