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A188296 Center element of a series of 5 successive nonsquarefree numbers. 2
846, 1682, 2890, 3626, 5048, 10926, 14750, 15850, 17406, 19942, 22022, 22023, 22626, 23274, 24649, 24650, 25774, 29350, 30250, 30925, 30926, 33174, 36702, 37250, 38726, 39446, 40474, 45374, 47674, 47675, 47726, 47826, 48374, 49490, 54586, 55026, 55449, 55450, 57122, 57123, 58474, 58850 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Each of a(n), a(n)-1, a(n)-2, a(n)+1, a(n)+2 has at least a square divisor.

LINKS

Table of n, a(n) for n=1..42.

EXAMPLE

846 = 2*3^2*47, 846 - 1 = 5*13^2, 846 - 2 = 2^2*211, 846 + 1 = 7*11^2, 846 + 2 = 2^4*53.

MATHEMATICA

Select[Range[1, 100000], !SquareFreeQ[#] &&!SquareFreeQ[#-1] &&!SquareFreeQ[#+1] &&!SquareFreeQ[#-2] &&!SquareFreeQ[#+2]&]

CROSSREFS

Cf. A005117, A013929.

Sequence in context: A078144 A071320 A160212 * A187861 A280484 A203335

Adjacent sequences:  A188293 A188294 A188295 * A188297 A188298 A188299

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Mar 29 2011

STATUS

approved

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Last modified June 28 20:39 EDT 2017. Contains 288840 sequences.