A050687 Numbers k such that A000422(k) is squarefree.

1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 16, 19, 20, 21, 22, 23, 24, 25, 28, 29, 30, 31, 32, 33, 34, 37, 38, 39, 40, 41, 42, 43, 46, 47, 48, 49, 50, 51, 52, 55, 57, 58, 59, 60, 61, 64, 65, 66, 67, 68, 69, 70, 73, 74, 75, 76, 77, 78, 79, 82, 83, 84, 85, 86, 87

Offset: 1

Author

Patrick De Geest, Aug 15 1999

Keywords

• nonn
• base
• hard

Links

• Patrick De Geest, Reversed Smarandache Concatenated Numbers, Prime factors from n down to 1
• M. Fleuren, Factors and primes of Smarandache sequences.
• M. Fleuren, Smarandache Factors and Reverse factors
• Carlos Rivera, Puzzle 8. Primes by Listing, The Prime Puzzles & Problems Connection.

Crossrefs

Cf. A000422, A048288, A048342, A050675, A050688.

Extensions

More terms from and name clarified by Sean A. Irvine, Aug 17 2021

Offset changed to 1 by Jinyuan Wang, Sep 04 2021