A064392 Numbers in A064383 that are squarefree.

1, 2, 5, 10, 13, 26, 37, 65, 74, 130, 185, 370, 463, 481, 926, 962, 2315, 2405, 4630, 4810, 6019, 12038, 17131, 30095, 34262, 60190, 85655, 171310, 222703

Offset: 1

Author

Jason Earls, Sep 28 2001

Keywords

• more
• nonn

Programs

PARI

for(n=1,10^6,x=sum(k=0,n,(-1)^k*k!); if(Mod(x,n)==0 && issquarefree(n),print(n)))

Extensions

a(17)-a(29) from Donovan Johnson, Nov 30 2008