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%I #7 Dec 02 2024 09:50:05
%S 3,2,1,0,3,2,1,0,0,2,1,0,3,2,1,0,1,0,1,0,3,2,1,0,0,1,0,0,3,2,1,0,3,2,
%T 1,0,3,2,1,0,3,2,1,0,0,2,1,0,0,0,1,0,1,0,1,0,3,2,1,0,2,1,0,0,3,2,1,0,
%U 3,2,1,0,2,1,0,0,3,2,1,0,0,2,1,0,3,2,1
%N Distance between n and the least nonsquarefree number >= n.
%C All terms are 0, 1, 2, or 3 (cf. A078147).
%t Table[NestWhile[#+1&,n,SquareFreeQ[#]&]-n,{n,100}]
%Y Adding n to each term a(n) gives A120327.
%Y Positions of 0 are A013929.
%Y Positions of 1 are A373415.
%Y Positions of 2 are A378458.
%Y Positions of 3 are A007675.
%Y Sequences obtained by adding n to each term are placed in parentheses below.
%Y The version for primes is A007920 (A007918).
%Y The version for perfect powers is A074984 (A377468).
%Y The version for squarefree numbers is A081221 (A067535).
%Y The version for non-perfect powers is A378357 (A378358).
%Y The version for prime powers is A378370 (A000015).
%Y The version for non prime powers is A378371 (A378372).
%Y A005117 lists the squarefree numbers, first differences A076259.
%Y A013929 lists the nonsquarefree numbers, first differences A078147.
%Y A120992 gives run-lengths of squarefree numbers increasing by one.
%Y Cf. A073247, A151800, A236575, A243348, A375707, A377046, A378033, A378039, A378086, A378373.
%K nonn
%O 1,1
%A _Gus Wiseman_, Dec 01 2024