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.

A067821 The start of a record-breaking run of consecutive integers with a number of prime factors (counted with multiplicity) equal to 6.

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%I A067821 #32 Aug 31 2025 12:55:17
%S A067821 64,5264,33614,8706123,101905622,4843161124,25189114374,412352139170,
%T A067821 1122875553872,28099912628847,78661670985666
%N A067821 The start of a record-breaking run of consecutive integers with a number of prime factors (counted with multiplicity) equal to 6.
%C A067821 a(11) > 3*10^13. - _Brian Trial_, May 26 2017
%C A067821 a(12) > 2 * 10^15. - _Toshitaka Suzuki_, Aug 31 2025
%e A067821 a(3)=33614 because 33614 is the start of a record breaking run of 3 consecutive integers (33614 to 33616) each having 6 prime factors; i.e., bigomega(n)=A001222(n)=6 for n = 33614, ..., 33616.
%t A067821 bigomega[n_] := Plus@@Last/@FactorInteger[n]; For[n=1; m=l=0, True, n++, If[bigomega[n]==6, l++, If[l>m, m=l; Print[n-l, " ", l]]; l=0]]
%Y A067821 Cf. A001222, A067813, A067814, A067820, A067822.
%K A067821 fini,more,nonn,changed
%O A067821 1,1
%A A067821 _Shyam Sunder Gupta_, Feb 07 2002
%E A067821 Edited by _Dean Hickerson_, Jul 31 2002
%E A067821 More terms from _Jens Kruse Andersen_, Aug 23 2003
%E A067821 a(7)-a(9) from _Donovan Johnson_, Jan 31 2009
%E A067821 a(10) from _Brian Trial_, May 26 2017
%E A067821 a(11) from _Toshitaka Suzuki_, Aug 31 2025