OFFSET
1,1
COMMENTS
First differs from its subsequence A082686 in a(16)=81 which is not in A082686. More precisely, A226025 \ A082686 = A062532 \ {1} = A014076^2 \ {1}. - M. F. Hasler, Oct 20 2013
Odd numbers that are greater than the square of their least prime factor - Odimar Fabeny, Sep 08 2014
LINKS
Arkadiusz Wesolowski, Table of n, a(n) for n = 1..10000
FORMULA
MAPLE
select(n -> not(isprime(n)) and (not(issqr(n)) or not(isprime(sqrt(n)))), [seq(2*i+1, i=1..1000)]); # Robert Israel, Sep 08 2014
MATHEMATICA
Select[Range[3, 217, 2], ! PrimeQ[#] && ! PrimeQ@Sqrt[#] &]
r = Prime@Range[2, 6]^2; Complement[Select[Range[3, Last[r] - 2, 2], ! PrimeQ[#] &], Most[r]]
Select[Range[3, 251, 2], NoneTrue[{#, Sqrt[#]}, PrimeQ]&] (* Harvey P. Dale, Sep 06 2021 *)
PROG
(Magma) [n: n in [3..217 by 2] | not IsPrime(n) and not IsSquare(n) or IsSquare(n) and not IsPrime(Floor(n^(1/2)))]
(Haskell)
a226025 n = a226025_list !! (n-1)
a226025_list = filter ((/= 2) . a100995) a071904_list
-- Reinhard Zumkeller, Jun 15 2013
(PARI) is_A226025(n)={bittest(n, 0)&&!isprime(n, 0)&&!(issquare(n)&&isprime(sqrtint(n)))&&n>1} \\ - M. F. Hasler, Oct 20 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Arkadiusz Wesolowski, Jun 07 2013
STATUS
approved