A251392 Indices of nonprimes in A098550.

1, 4, 5, 6, 7, 8, 10, 11, 12, 13, 14, 16, 17, 18, 19, 20, 21, 24, 25, 26, 27, 28, 29, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 44, 45, 46, 47, 48, 49, 50, 52, 53, 54, 55, 56, 57, 58, 59, 60, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77

Offset: 1

Author

Reinhard Zumkeller, Dec 03 2014

Keywords

• nonn

Comments

A010051(A098550(a(n))) = 0; A239968(A098550(a(n))) > 0;

three equivalent statements:

1) A098550 is a permutation of the positive integers, cf. A000027;

2) A251392 is a permutation of the nonprimes, cf. A018252;

3) A251392 is the complement of A251239.

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A098550, A018252, A010051, A239968, A251239, A251240 (subsequence).

Programs

Haskell

a251392 n = a251392_list !! (n-1)
a251392_list = filter ((== 0) . a010051' . a098550) [1..]