A071577 Smallest k such that 2ik+1 is squarefree for 1<=i<=n.

1, 1, 1, 5, 5, 5, 5, 9, 9, 9, 9, 9, 9, 9, 9, 63, 63, 63, 63, 63, 63, 63, 63, 135, 135, 135, 135, 135, 135, 135, 135, 135, 135, 135, 135, 135, 135, 135, 135, 135, 135, 135, 135, 735, 735, 735, 945, 945, 945, 1155, 1155, 1155, 1155, 1155, 1155, 1155

Offset

1,4

Links

Table of n, a(n) for n=1..56.

Prog

(PARI) for(n=1, 56, s=1; while(sum(i=1, n, issquarefree(2*i*s+1))<n, s++); print1(s, ", "))

Crossrefs

Sequence in context: A240233 A033299 A293982 * A003870 A304681 A076407

Adjacent sequences: A071574 A071575 A071576 * A071578 A071579 A071580

Keyword

easy,nonn

Author

Benoit Cloitre, May 31 2002

Status

approved