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A233444 Primes that are exactly halfway between the nearest square and the nearest cube. 1
2203, 90863, 185477, 388573, 613607, 912349, 1293899, 1600919, 2146457, 30661333, 35608189, 81190429, 105823093, 122753857, 204341747, 338602837, 368601707, 374788121, 426958673, 498675409, 586371239, 656232799, 665360321, 674509487, 693132527, 1102304669, 1180942709 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A subsequence of A233075.

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

MAPLE

Res:= NULL:

for x from 3 to 2000 do

  x3:= x^3;

  y:= floor(sqrt(x3));

  p:= (x3+y^2)/2;

  if p::integer and x3-p <= p - (x-1)^3 and p - y^2 <= (y+1)^2-p and isprime(p) then

    Res:= Res, p;

  fi;

  p:= (x3+(y+1)^2)/2;

  if p::integer and p-x3 <= (x+1)^3-p and (y+1)^2-p <= p - y^2 and isprime(p) then

      Res:= Res, p;

  fi

od:

Res; # Robert Israel, May 01 2018

CROSSREFS

Cf. A000040, A000290, A000578, A233075.

Cf. A002760 (Squares and cubes).

Sequence in context: A044989 A202894 A075455 * A125015 A252397 A252392

Adjacent sequences:  A233441 A233442 A233443 * A233445 A233446 A233447

KEYWORD

nonn

AUTHOR

Alex Ratushnyak, Dec 09 2013

STATUS

approved

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Last modified June 25 21:43 EDT 2019. Contains 324357 sequences. (Running on oeis4.)