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A093739 Number of prime pairs below 10^n having a difference of 8. 2
0, 1, 15, 101, 773, 5569, 42352, 334180, 2695109, 22160841, 185402143, 1573331564, 13515180171, 117333792953, 1028087693781, 9081524454631, 80799078096971, 723494891844589 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

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

Siegfried "Zig" Herzog, Frequency of Occurrence of Prime Gaps

T. Oliveira e Silva, S. Herzog, and S. Pardi, Empirical verification of the even Goldbach conjecture and computation of prime gaps up to 4.10^18, Math. Comp., 83 (2014), 2033-2060.

EXAMPLE

a(3) = 15 because there are 15 prime gaps of 8 below 10^3.

PROG

(UBASIC)

20 N=1:dim T(34);

30 A=nxtprm(N);

40 N=A;

50 B=nxtprm(N);

60 D=B-A;

70 for x=2 to 34 step 2;

80 if D=X and B<10^2+1 then T(X)=T(X)+1;

90 next X;

100 if B>10^2+1 then 140;

110 B=A;

120 N=N+1;

130 goto 30;

140 for x=2 to 34 step 2;

150 print T(X); ,

160 next

## (This program simultaneously finds values from 2 to 34 - if gap=2 add 1- adjust lines 80 and 100 for desired 10^n)

CROSSREFS

Cf. A007508, A093738, A093740.

Sequence in context: A242657 A163717 A111370 * A205431 A085465 A205424

Adjacent sequences:  A093736 A093737 A093738 * A093740 A093741 A093742

KEYWORD

nonn,more

AUTHOR

Enoch Haga, Apr 15 2004

EXTENSIONS

a(10)-a(13) from Washington Bomfim, Jun 20 2012

a(14)-a(18) from S. Herzog's website added by Giovanni Resta, Aug 14 2018

STATUS

approved

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Last modified April 16 09:04 EDT 2021. Contains 343030 sequences. (Running on oeis4.)