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.

A046467 Numbers k such that the concatenation of numbers from 1 to k is the product of 8 primes (not necessarily distinct).

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%I A046467 #23 Apr 10 2021 16:59:40
%S A046467 6,21,27,35,48,53,60,62,66,92,106,108,117
%N A046467 Numbers k such that the concatenation of numbers from 1 to k is the product of 8 primes (not necessarily distinct).
%H A046467 Patrick De Geest, <a href="http://www.worldofnumbers.com/factorlist.htm">Normal Smarandache Concatenated Numbers, Prime factors from 1 up to n</a>
%H A046467 M. Fleuren, <a href="http://www.gallup.unm.edu/~smarandache/micha.txt">Smarandache Factors and Reverse factors</a>
%H A046467 Carlos Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_008.htm">Puzzle 8. Primes by Listing</a>, The Prime Puzzles & Problems Connection.
%t A046467 Select[Range[100], PrimeOmega@FromDigits@Flatten@IntegerDigits@Range@# == 8 &] (* _Robert Price_, Oct 11 2019 *)
%Y A046467 Cf. A046460.
%K A046467 nonn,base,hard,more
%O A046467 1,1
%A A046467 _Patrick De Geest_, Aug 15 1998
%E A046467 a(9)-a(13) from _Sean A. Irvine_, Apr 10 2021