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A276567 Odd squares not of the form p + 2^k with p prime. 1
1, 40401, 62001, 96721, 121801, 192721, 326041, 410881, 555025, 660969, 683929, 772641, 786769, 822649, 1343281, 1390041, 1530169, 1739761, 1885129, 1923769, 1962801, 2283121, 2544025, 2913849, 3207681, 3214849, 3352561, 3396649, 3613801, 3775249, 3853369, 4060225 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The sequence contains also SierpiƄski numbers (i.e., 4521731193704761, 60428287050225649).

LINKS

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

FORMULA

A006285 INTERSECT A016754.

MAPLE

filter:= proc(n) local k;

   for k from 0 to ilog2(n) do

     if isprime(n - 2^k) then return false fi

   od:

   true

end proc:

select(filter, [seq((2*i+1)^2, i=0..10^4)]); # Robert Israel, Sep 07 2016

PROG

(MAGMA) lst:=[]; for s in [1..2015 by 2] do n:=s^2; x:=0; repeat x+:=1; a:=n-2^x; until a lt 1 or IsPrime(a); if a lt 1 then Append(~lst, n); end if; end for; lst;

CROSSREFS

Cf. A006285, A016754.

Sequence in context: A229675 A250905 A250949 * A216291 A216290 A237970

Adjacent sequences:  A276564 A276565 A276566 * A276568 A276569 A276570

KEYWORD

nonn

AUTHOR

Arkadiusz Wesolowski, Sep 06 2016

STATUS

approved

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Last modified October 21 12:12 EDT 2019. Contains 328299 sequences. (Running on oeis4.)