A077156 a(0) = 1, followed by next n primes followed by next n composite numbers.

1, 2, 4, 3, 5, 6, 8, 7, 11, 13, 9, 10, 12, 17, 19, 23, 29, 14, 15, 16, 18, 31, 37, 41, 43, 47, 20, 21, 22, 24, 25, 53, 59, 61, 67, 71, 73, 26, 27, 28, 30, 32, 33

Offset

0,2

Comments

A permutation of the natural numbers.

Links

Harvey P. Dale, Table of n, a(n) for n = 0..1000

Mathematica

Module[{nn=10, prs, cmps, len}, prs=Prime[Range[(nn(nn+1))/2]]; cmps= Select[ Range[ Max[ prs]], CompositeQ]; Join[{1}, Riffle[ TakeList[prs, Range[nn]], TakeList[ cmps, Range[ nn]]]]]// Flatten (* Harvey P. Dale, Apr 29 2022 *)

Crossrefs

Cf. A077157.

Sequence in context: A095689 A083194 A105366 * A258076 A244724 A132948

Adjacent sequences: A077153 A077154 A077155 * A077157 A077158 A077159

Keyword

easy,nonn

Author

Amarnath Murthy, Oct 31 2002

Status

approved