A023190 Conjecturally, maximum number of primes in an infinitely-recurring prime pattern of width 2*n-1.

1, 2, 2, 3, 4, 4, 5, 5, 6, 6, 7, 6, 7, 8, 8, 9, 10, 10, 11, 10, 11, 12, 12, 12, 13, 14, 13, 14, 15, 15, 16, 16, 16, 17, 17, 18, 18, 18, 19, 19, 20, 20, 21, 21, 21, 22, 22, 23, 23, 23, 24, 24, 24, 24, 24, 25, 25, 26, 26, 26, 27, 27, 27, 28, 28, 29, 29, 29, 30, 30

Offset

1,2

Comments

Of all the patterns in A023192 (i.e. infinitely-recurring prime patterns) for length 2*n-1, consider those starting and ending with "p". This sequence gives the maximal count of "p"'s in any of those patterns. The companion sequence A023191, gives the number of patterns achieving that maximum. - Sean A. Irvine, May 27 2019

Links

Martin Raab, Table of n, a(n) for n = 1..1166

Thomas J Engelsma, Permissible Patterns

Example

a(3) concerns patterns of length 5. Of the 10 potential patterns (ccccc, ccccp, cccpc, ccpcc, cpccc, pcccc, ccpcp, cpcpc, pcpcc, pcccp), only pcccp starts and ends with a "p", and it contains 2 "p"'s, so a(3) = 2, and A023191(3) = 1. - Sean A. Irvine, May 27 2019

Crossrefs

Cf. A023191, A023192.

Sequence in context: A227737 A194177 A348386 * A047783 A321667 A194212

Adjacent sequences: A023187 A023188 A023189 * A023191 A023192 A023193

Keyword

nonn

Author

David W. Wilson

Extensions

More terms from Thomas J Engelsma web page added by Martin Raab, Oct 31 2021

Status

approved