A233444 Primes that are exactly halfway between the nearest square and the nearest cube.

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

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 A348743 A252397

Adjacent sequences: A233441 A233442 A233443 * A233445 A233446 A233447

Keyword

nonn

Author

Alex Ratushnyak, Dec 09 2013

Status

approved