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 1-3 of 3 results.

A332313 Numbers k such that k, k + 1 and k + 2 have the same number of divisors in Gaussian integers.

Original entry on oeis.org

23824, 38574, 52974, 62224, 71406, 105424, 110574, 191824, 201616, 209424, 240174, 249775, 282896, 285102, 297774, 326574, 340974, 375824, 393424, 407824, 440656, 451024, 496174, 509776, 553774, 587536, 599632, 600174, 606032, 623824, 628974, 631376, 667024, 672174
Offset: 1

Views

Author

Amiram Eldar, Feb 09 2020

Keywords

Examples

			23824 is a term since 23824, 23825 and 23826 each have 36 divisors in Gaussian integers.
		

Crossrefs

Programs

  • Mathematica
    Flatten[Position[Partition[DivisorSigma[0, Range[3*10^5], GaussianIntegers -> True], 3, 1], {x_, x_, x_}]] (* after Harvey P. Dale at A005238 *)

A332386 Numbers k such that k and k + 1 have the same number of divisors in Eisenstein integers.

Original entry on oeis.org

3, 7, 32, 50, 68, 174, 184, 200, 212, 219, 247, 291, 328, 343, 368, 376, 435, 472, 495, 543, 579, 608, 644, 679, 712, 716, 723, 788, 795, 849, 860, 871, 874, 904, 932, 939, 1011, 1015, 1058, 1074, 1076, 1159, 1184, 1220, 1227, 1336, 1359, 1384, 1436, 1495, 1515
Offset: 1

Views

Author

Amiram Eldar, Feb 10 2020

Keywords

Examples

			3 is a term since 3 and 4 both have 3 divisors in Eisenstein integers.
		

Crossrefs

Programs

  • Mathematica
    f[p_, e_] := Switch[Mod[p, 3], 0, 2*e + 1, 1, (e + 1)^2, 2, e + 1]; eisNumDiv[1] = 1; eisNumDiv[n_] := Times @@ f @@@ FactorInteger[n]; SequencePosition[eisNumDiv /@ Range[1520], {x_, x_}][[All, 1]] (* after Harvey P. Dale at A005237 *)

A332314 Numbers k such that k, k + 1, k + 2 and k + 3 have the same number of divisors in Gaussian integers.

Original entry on oeis.org

263449773, 334047725, 760228973, 862305773, 1965540624, 2136055725, 2362380525, 2477365422, 2515570575, 2613782223, 2939626925, 3181603023, 3814526223, 3987335022, 4610697039, 4771214574, 4981539822, 5018728272, 5035157775, 5186567824, 6189727725, 6329159823, 6569396973
Offset: 1

Views

Author

Amiram Eldar, Feb 09 2020

Keywords

Examples

			263449773 is a term since 263449773, 263449774, 263449775 and 263449776 each have 72 divisors in Gaussian integers.
		

Crossrefs

Programs

  • Mathematica
    gaussNumDiv[n_] := DivisorSigma[0, n, GaussianIntegers -> True]; m = 4; s = gaussNumDiv /@ Range[m]; seq = {}; n = m + 1; While[Length[seq] < 10, If[Length @ Union[s] == 1, AppendTo[seq, n - m + 1]]; n++; s = Join[Rest[s], {gaussNumDiv[n]}]]; seq
Showing 1-3 of 3 results.