login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A064281 Least k such that k*10^n+1, k*10^n+3, k*10^n+7 and k*10^n+9 are all prime. 3
4, 1, 1, 13, 676, 283, 14311, 12022, 27346, 14965, 3427, 100942, 12370, 1237, 3274, 42382, 18619, 4570, 457, 434869, 203362, 305491, 213742, 436831, 217198, 168586, 258214, 215737, 1312441, 272848, 744082, 2059111, 351055, 712333, 1880302 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..34.

MATHEMATICA

Do[k = 1; While[ !PrimeQ[k*10^n + 1] || !PrimeQ[k*10^n + 3] || !PrimeQ[k*10^n + 7] || !PrimeQ[k*10^n + 9], k++ ]; Print[k], {n, 0, 20} ]

CROSSREFS

Sequence in context: A212801 A147565 A022167 * A267318 A050154 A179454

Adjacent sequences:  A064278 A064279 A064280 * A064282 A064283 A064284

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Oct 14 2001

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 16 00:11 EST 2018. Contains 317252 sequences. (Running on oeis4.)