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A071808
Smallest s such that sk+1 is squarefree for 1 <= k <= n.
0
1, 1, 2, 10, 10, 10, 10, 18, 18, 18, 18, 18, 18, 18, 18, 126, 126, 126, 126, 126, 126, 126, 126, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 1470, 1470, 1470, 1890, 1890, 1890, 2310, 2310, 2310, 2310
OFFSET
1,3
COMMENTS
a(n)+1 or a(n)-1 is prime for listed terms.
PROG
(PARI) for(n=1, 57, s=1; while(sum(i=1, n, issquarefree(s*i+1))<n, s++); print1(s, ", "))
CROSSREFS
Sequence in context: A215463 A066556 A156556 * A355486 A168381 A212621
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, Jun 06 2002
STATUS
approved