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A077681
Squarefree numbers beginning with 5.
12
5, 51, 53, 55, 57, 58, 59, 501, 502, 503, 505, 506, 509, 510, 511, 514, 515, 517, 518, 519, 521, 523, 526, 527, 530, 533, 534, 535, 537, 538, 541, 542, 543, 545, 546, 547, 551, 553, 554, 555, 557, 559, 561, 562, 563, 565, 566, 569, 570, 571, 573, 574, 577
OFFSET
1,1
COMMENTS
Lower density is 3/(25*Pi^2), upper density is 10/(9*Pi^2). - Charles R Greathouse IV, Nov 05 2017
LINKS
MATHEMATICA
Table[Select[Range[5*10^n, 6*10^n-1], SquareFreeQ], {n, 0, 2}]//Flatten (* Harvey P. Dale, Apr 15 2017 *)
PROG
(PARI) is(n)=n>4 && digits(n)[1]==5 && issquarefree(n) \\ Charles R Greathouse IV, Nov 05 2017
KEYWORD
base,easy,nonn
AUTHOR
Amarnath Murthy, Nov 16 2002
EXTENSIONS
More terms from Sascha Kurz, Jan 28 2003
STATUS
approved