A240592 Number of primes between successive composite squarefree numbers (A120944).
1, 2, 0, 2, 0, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 0, 0, 2, 0, 0, 1, 0, 2, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 2, 1, 0, 2, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 1, 0, 0, 0, 0, 2, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 2, 0, 0, 0, 0, 0, 2, 0, 2, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0
Offset: 1
Keywords
Examples
a(4) is 2 because A120944(4)=15, A120944(5)=21, 2 primes between them: 17 and 19.
Programs
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PARI
freesqrcomp(n)=issquarefree(n)&&!isprime(n) nextfqc(n)={local(k);k=n+1;while(!freesqrcomp(k),k+=1);return(k)} primesin(a,b)={local(p=a,q=0);while(p
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