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 A329203 Numbers n such that A329308(n)=0. 1
 1, 2, 3, 4, 5, 8, 9, 13, 17, 24, 33, 40, 64, 76, 108, 116, 208, 220, 324, 496, 504, 564, 1176 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Numbers n such that there is no k < sqrt(n) for which n mod (k^2) is prime. No more terms up to 2*10^7.  I conjecture that these are all the terms. LINKS EXAMPLE a(7) = 17 is in the sequence because 17 mod (2^2) = 1, 17 mod (3^2) = 8 and 17 mod (4^2) = 1 are all nonprime while 5^2 > 17. 20 is not in the sequence because 20 mod (3^2) = 2 is prime and 3^2 < 20. MAPLE filter:= proc(n) local k;   for k from 2 to floor(sqrt(n)) do if isprime(n mod k^2) then return false fi od:   true end proc: select(filter, [\$1..10^6]); PROG (MAGMA) [m:m in [1..2000]| #[k:k in [2..Floor(Sqrt(m))]| IsPrime(m mod k^2) ] eq 0]; // Marius A. Burtea, Nov 11 2019 CROSSREFS Cf. A329308. Sequence in context: A094103 A317082 A268359 * A054181 A329563 A163077 Adjacent sequences:  A329200 A329201 A329202 * A329204 A329205 A329206 KEYWORD nonn,more AUTHOR Robert Israel, Nov 10 2019 STATUS approved

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Last modified June 5 14:36 EDT 2020. Contains 334841 sequences. (Running on oeis4.)