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A098968 Record values for size of sea of composite numbers surrounding primes. 2
0, 1, 2, 4, 8, 10, 12, 16, 22, 26, 38, 40, 42, 46, 48, 54, 56, 70, 74, 78, 80, 98, 112, 114, 124, 136, 138, 158, 188, 198, 232, 234, 244, 246, 268, 304, 326, 328, 334, 338, 370 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

For a prime p let s(p) (essentially A046930) denote the number of composite numbers less than p and greater than max{1, previous prime} or greater than p and less than the next prime. Sequence gives record values of s(p).

LINKS

Table of n, a(n) for n=0..40.

MATHEMATICA

a = {1, 2}; b = {0, 1}; d = 1; p = 2; q = 3; Do[ r = Prime[n]; c = r - p - 2; If[c > d, Print[{n + 1, c}]; d = c; AppendTo[a, n - 1]; AppendTo[b, c]]; p = q; q = r, {n, 3, 10^9}]; b (* Robert G. Wilson v, Oct 27 2004 *)

CROSSREFS

Records in A046930 (if initial term is 0 not 1). Cf. A098969, A046931.

Sequence in context: A166245 A276623 A121519 * A032368 A134533 A089953

Adjacent sequences:  A098965 A098966 A098967 * A098969 A098970 A098971

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Oct 24 2004

EXTENSIONS

More terms from Robert G. Wilson v and Olaf Voß, Oct 27 2004

STATUS

approved

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Last modified November 22 16:26 EST 2019. Contains 329396 sequences. (Running on oeis4.)