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A192226 Numbers n such that all integers in the interval (n-2*sqrt(sqrt(n)), n] are composite. 3
1, 28, 36, 96, 120, 121, 122, 123, 124, 125, 126, 146, 147, 148, 189, 190, 207, 208, 209, 210, 219, 220, 221, 222, 249, 250, 292, 302, 303, 304, 305, 306, 326, 327, 328, 329, 330, 346, 477, 478, 519, 520, 533, 534, 535, 536, 537, 538, 539, 540, 630, 672 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(14432) = 191913030 is probably the last term. Any further terms must be greater than 1.5 * 10^18. - Charles R Greathouse IV, Jun 30 2011

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..14432

MATHEMATICA

Select[Range[700], NextPrime[#-2Sqrt[Sqrt[#]]]>#&] (* Harvey P. Dale, Jul 27 2011 *)

PROG

(PARI) is(n)=for(k=0, sqrtnint(16*n-1, 4), if(isprime(n-k), return(0))); 1 \\ Charles R Greathouse IV, Aug 26 2015

CROSSREFS

Cf. A188817, A189025, A008995.

Sequence in context: A061900 A048023 A105710 * A323005 A080983 A179105

Adjacent sequences:  A192223 A192224 A192225 * A192227 A192228 A192229

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Jun 26 2011

EXTENSIONS

a(12)-a(13) added, a(53)-a(56) corrected by Charles R Greathouse IV, Jun 30 2011

STATUS

approved

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Last modified March 29 15:16 EDT 2020. Contains 333107 sequences. (Running on oeis4.)