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A073861 Smaller of pair of successive n-digit primes with maximal difference. 4
3, 89, 887, 9551, 31397, 492113, 4652353, 47326693, 436273009, 4302407359, 42652618343, 738832927927, 7177162611713, 90874329411493, 218209405436543, 1693182318746371, 80873624627234849, 804212830686677669 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A subsequence of A002386 (assuming that there is an n-digit term in A002386 for all values of n). - M. F. Hasler, Apr 28 2014

LINKS

Table of n, a(n) for n=1..18.

Thomas R. Nicely, First occurrence prime gaps

FORMULA

A073861 = A000040 o A241623. - M. F. Hasler, Apr 28 2014

a(n) = max { p in A002386 | nextprime(p) < 10^n } (under the assumption given in the comment). - M. F. Hasler, Apr 28 2014

EXAMPLE

a(3) = 887, the next prime is 907, 907-887=20 is the maximal possible difference of two 3-digit primes and no smaller pair exhibits this property.

MATHEMATICA

Table[Last[Sort[{#[[2]]-#[[1]], #[[1]], #[[2]]}&/@Partition[Prime[Range[PrimePi[10^i]+1, PrimePi[10^(i+1)]]], 2, 1]]][[2]], {i, 7}] (* Harvey P. Dale, Jan 23 2010 *)

CROSSREFS

Sequence in context: A106944 A142252 A159508 * A134502 A116336 A254083

Adjacent sequences:  A073858 A073859 A073860 * A073862 A073863 A073864

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Aug 15 2002

EXTENSIONS

Corrected error and added terms Harvey P. Dale, Jan 23 2010

a(9)-a(18) from Donovan Johnson, Nov 29 2010

STATUS

approved

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Last modified August 6 12:33 EDT 2020. Contains 336246 sequences. (Running on oeis4.)