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.

A323083 k-digit numbers whose digit(s) are the number of distinct prime factors in each of the following k integers.

Original entry on oeis.org

0, 1, 12, 21, 22422, 24223, 33333, 34441524, 4242436235, 23443535352, 34462443242, 35256523324, 4341535435353, 4645441523344, 5244526446515, 5335524234335
Offset: 1

Views

Author

G. L. Honaker, Jr., Jan 03 2019

Keywords

Comments

a(9) = 4242436235 found by Carlos Rivera.
a(17) > 10^13. - Giovanni Resta, Jan 04 2019

Examples

			21 is a term because 21 is a 2-digit number and its digits (2,1) are the number of distinct prime factors in each of the following 2 integers; i.e., 22 = 2*11 (two distinct prime factors) and 23 = 23 (one distinct prime factor), therefore (2,1) -> 21.
		

Crossrefs

Programs

  • PARI
    isok(m) = {my(d=digits(m)); for (i=1, #d, if (d[i] != omega(m+i), return(0));); return (1);}  \\ Michel Marcus, Oct 11 2021

Extensions

a(10)-a(16) from Giovanni Resta, Jan 04 2019