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A094660 Number of permissible patterns of primes in a fixed interval. 1
0, 1, 2, 4, 6, 9, 12, 18, 24, 34, 44, 58, 72, 100, 128, 169, 210, 267, 324, 429, 534, 694, 854, 1064, 1274, 1657, 2040, 2571, 3102, 3780, 4458, 5801, 7144, 9067, 10990, 13472, 15954, 20356, 24758, 30607, 36456, 44280 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

pp(w)=w+sumi(sumj((w-i+1)*pb(j,i)) were pb(j,i) is A023189.

Similar to A023192. (Here we ignore the empty pattern and start at 0.) These are called "admissible constellations" of primes. - Don Reble, Jun 12 2004.

LINKS

Table of n, a(n) for n=0..41.

Similar work at Permissible Patterns

EXAMPLE

pp(5)=9 because primes can exist in interval as x.... .x... ..x.. ...x. ....x x.x.. .x.x. ..x.x or x...x

CROSSREFS

Cf. A008407, A020497, A023189. Equals A023192 - 1.

Sequence in context: A079492 A267161 A173784 * A005690 A005779 A261417

Adjacent sequences:  A094657 A094658 A094659 * A094661 A094662 A094663

KEYWORD

nonn

AUTHOR

Thomas J Engelsma (tom(AT)opertech.com), Jun 09 2004

STATUS

approved

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Last modified December 6 22:42 EST 2021. Contains 349567 sequences. (Running on oeis4.)