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A172357 n such that the Liouville function lambda(n) take successively, from n, the values 1,-1,1,-1,1,-1.

%I A172357 #21 Aug 10 2025 19:31:16
%S A172357 58,185,194,274,287,342,344,382,493,566,667,856,858,926,1012,1014,
%T A172357 1157,1165,1230,1232,1234,1267,1318,1385,1393,1418,1482,1484,1679,
%U A172357 1681,1795,1841,1915,1917,2060,2062,2064,2232,2340,2342,2567,2569,2627,2805,3013
%N A172357 n such that the Liouville function lambda(n) take successively, from n, the values 1,-1,1,-1,1,-1.
%H A172357 Harvey P. Dale, <a href="/A172357/b172357.txt">Table of n, a(n) for n = 1..1000</a>
%p A172357 with(numtheory): for n from 1 to 4300 do;if (-1)^bigomega(n)=1 and (-1)^bigomega(n+1) = -1 and (-1)^bigomega(n+2) = 1 and (-1)^bigomega(n+3) = -1 and (-1)^bigomega(n+4) = 1 and (-1)^bigomega(n+5) = -1 then print(n); else fi ; od;
%t A172357 Transpose[Transpose[#][[1]]&/@Select[Partition[Table[{n, LiouvilleLambda[ n]},{n,3100}],6,1],Transpose[#][[2]]=={1,-1,1,-1,1,-1}&]][[1]] (* _Harvey P. Dale_, May 19 2012 *)
%o A172357 (PARI) lambda(n)=(-1)^bigomega(n);
%o A172357 for(n=1,1e4,if(lambda(n)==1&lambda(n+1)==-1&lambda(n+2)==1&&lambda(n+3)==-1&lambda(n+4)==1&&lambda(n+5)==-1,print1(n", "))) /* _Charles R Greathouse IV_, Jun 13 2011 */
%Y A172357 Cf. A051470, A028488, A002819.
%K A172357 nonn
%O A172357 1,1
%A A172357 _Michel Lagneau_, Feb 01 2010