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A088068
Squares sandwiched between two numbers divisible by squares.
2
49, 1681, 1849, 3249, 6724, 8649, 9801, 11449, 13689, 13924, 20449, 24649, 28224, 37249, 42849, 57121, 59049, 63001, 66049, 85849, 94249, 106929, 110224, 117649, 127449, 135424, 154449, 165649, 190969, 196249, 208849, 243049, 257049, 265225
OFFSET
1,1
COMMENTS
Sequence is infinite. k^2 is a member if k == 7 (mod 50), or k == -7 (mod 50).
EXAMPLE
49 is a term as 48 and 50 are divisible by squares.
MATHEMATICA
okQ[n_]:=Max[Transpose[FactorInteger[n]][[2]]]>1; Select[Range[600]^2, okQ[#-1]&&okQ[#+1]&] (* Harvey P. Dale, Jan 26 2011 *)
CROSSREFS
Cf. A088069.
Sequence in context: A004374 A203500 A069327 * A140394 A008843 A145848
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Sep 22 2003
EXTENSIONS
Corrected and extended by Ray Chandler, Sep 27 2003
STATUS
approved