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.

A364435 The first term in a run of at least 4 consecutive numbers each with exactly 5 distinct prime factors (i.e. belong to A051270).

Original entry on oeis.org

21871365, 37055184, 37227993, 39272583, 41205603, 43067463, 44012682, 44126949, 47761635, 48806274, 49362234, 49613484, 50582103, 52953795, 54244068, 60529077, 60988653, 61042069, 62319465, 63850344, 66068793, 66709683, 66710004, 67874079, 67974312, 68294148, 68529900
Offset: 1

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Author

David A. Corneth, Jul 24 2023

Keywords

Examples

			21871365 is in the sequence as it starts a run of at least 4 consecutive numbers each with exactly 5 distinct prime factors.
That is each of 21871365 = 3 * 5 * 29 * 137 * 367, 21871365 + 1 = 21871366 = 2 * 11 * 37 * 97 * 277, 21871365 + 2 = 21871367 = 7*17*23*61*131, 21871365 + 3 = 21871368 = 2^3 * 3^2 * 31 * 41 * 239 have 5 distinct prime factors.
		

Crossrefs

Programs

  • PARI
    upto(n) = {my(res = List(), streak = 0); n+=3; forfactored(i = 1, n, if(omega(i[2]) == 5, streak++; if(streak >= 4, listput(res, i[1]-3)), streak = 0)); res}