A332534 Numbers that are not of the form prime + 2^(2^k) + m! with k >= 0, m >= 0.

1, 2, 3, 4, 38, 68, 80, 98, 122, 128, 146, 150, 158, 164, 188, 192, 206, 212, 218, 220, 222, 224, 248, 252, 278, 290, 292, 302, 306, 308, 326, 332, 338, 344, 368, 374, 380, 398, 410, 416, 428, 432, 440, 458, 476, 488, 500, 510, 518, 522, 530, 532, 536, 542

Offset

1,2

Links

Alois P. Heinz, Table of n, a(n) for n = 1..10000

Christian Elsholtz, Florian Luca, and Stefan Planitzer, Romanov type problems, The Ramanujan Journal 47.2 (2018): 267-289.

Maple

q:= proc(n) local k, m;
      for k from 0 while 2^(2^k)<n do
        for m while 2^(2^k)+m!<n do
          if isprime(n-2^(2^k)-m!) then return false fi:
        od
      od; true
    end:
select(q, [$1..600])[];  # Alois P. Heinz, Feb 15 2020

Mathematica

q[n_] := Module[{k, m}, For[k = 0, 2^(2^k) < n, k++, For[m = 1, 2^(2^k) + m! < n, m++, If[PrimeQ[n - 2^(2^k) - m!] , Return[False]]]]; True];
Select[Range[600], q] (* Jean-François Alcover, Nov 26 2020, after Alois P. Heinz *)

Crossrefs

Cf. A218044, A332379, A332535.

Sequence in context: A308045 A247961 A294921 * A293685 A078394 A375477

Adjacent sequences: A332531 A332532 A332533 * A332535 A332536 A332537

Keyword

nonn

Author

N. J. A. Sloane, Feb 15 2020

Status

approved