A232805 a(n) is the length of the n-th chunk of nonprimes in this sequence, the chunks being separated by primes; lexicographically least such sequence starting with a prime.

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

Offset

1,1

Comments

Another self-describing sequence invented by E. Angelini. Conjectured to be a permutation of the positive integers.

The position of the primes are given in A232807.

See A232846 for the lexicographically smaller variant starting with a nonprime.

Links

Table of n, a(n) for n=1..66.

E. Angelini, Self-describing chunks of primes, SeqFan list, Nov 30 2013

Prog

(PARI) my(a=[], i=0, p=0, c=0); while(#a<99, a=concat(a, p=nextprime(p+1)); for(j=1, a[i++], while(isprime(c++), ); a=concat(a, c))); a

Crossrefs

Cf. A232807, A232846.

Sequence in context: A282651 A282665 A320283 * A361740 A073672 A306230

Adjacent sequences: A232802 A232803 A232804 * A232806 A232807 A232808

Keyword

nonn

Author

M. F. Hasler and Eric Angelini, Nov 30 2013

Status

approved