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A084976 Values of k that show the slow decrease in the larger values of the Andrica function Af(k) = sqrt(p(k+1)) - sqrt(p(k)), where p(k) denotes the k-th prime. 4
4, 30, 217, 263, 367, 429, 462, 590, 650, 738, 3385, 3644, 4522, 4612, 5949, 14357, 31545, 40933, 49414, 104071, 118505, 149689, 157680, 165326, 325852, 415069, 491237, 566214, 597311, 733588, 1319945, 1736516, 2850174, 2857960, 3183065 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n) are values of k such that Af(k) > Af(m) for all m > k. This sequence relies on a heuristic calculation and there is no proof that it is correct.

REFERENCES

R. K. Guy, "Unsolved Problems in Number Theory", Springer-Verlag 1994, A8, p. 21.

P. Ribenboim, "The Little Book of Big Primes", Springer-Verlag 1991, p. 143.

LINKS

H. J. Smith, Table of n, a(n) for n=1..128

H. J. Smith, Andrica's Conjecture

Eric Weisstein's World of Mathematics, Andrica's conjecture.

EXAMPLE

a(3)=217 because p(217)=1327, p(218)=1361 and Af(217) =sqrt(1361) - sqrt(1327) = 0.463722... is larger than any value of Af(m)for m>217.

CROSSREFS

Cf. A078693, A079098, A079296, A084974, A084975, A084977.

Sequence in context: A094567 A134093 A007905 * A000313 A082144 A220727

Adjacent sequences:  A084973 A084974 A084975 * A084977 A084978 A084979

KEYWORD

nonn

AUTHOR

Harry J. Smith, Jun 16 2003

STATUS

approved

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Last modified April 20 03:02 EDT 2021. Contains 343121 sequences. (Running on oeis4.)