A137621 Divisors of nonprimes not occurring earlier.

1, 2, 4, 3, 6, 8, 9, 5, 10, 12, 7, 14, 15, 16, 18, 20, 21, 11, 22, 24, 25, 13, 26, 27, 28, 30, 32, 33, 17, 34, 35, 36, 19, 38, 39, 40, 42, 44, 45, 23, 46, 48, 49, 50, 51, 52, 54, 55, 56, 57, 29, 58, 60, 31, 62, 63, 64, 65, 66, 68, 69, 70, 72, 37, 74, 75, 76, 77, 78, 80, 81, 41

Offset

1,2

Comments

Permutation with inverse A137622; A137623(n) = a(a(n)).

a(A120632(n))=A000040(n); a(A120632(n)+1)=A100484(n); a(A137624(n))=A018252(n).

Links

R. Zumkeller, Table of n, a(n) for n = 1..10001

Index entries for sequences that are permutations of the natural numbers

Example

1;2,4;3,6;8;9;5,10;12;7,14;15;16;18;20;21;11,22;24; .. .

Crossrefs

Sequence in context: A266411 A264740 A349370 * A242705 A350748 A357910

Adjacent sequences: A137618 A137619 A137620 * A137622 A137623 A137624

Keyword

nonn

Author

Reinhard Zumkeller, Jan 30 2008

Status

approved