login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A030473
Primes which are concatenations of 4 consecutive primes.
7
2357, 67717379, 838997101, 139149151157, 149151157163, 383389397401, 503509521523, 557563569571, 577587593599, 587593599601, 601607613617, 613617619631, 727733739743, 937941947953, 1181118711931201
OFFSET
1,1
LINKS
Zak Seidov and Robert Israel, Table of n, a(n) for n = 1..10000 (n = 1..1205 from Zak Seidov)
MAPLE
P:= select(isprime, [2, seq(p, p=3..10^4, 2)]):
select(isprime, [seq(P[i+3]+10^(1+ilog10(P[i+3]))*P[i+2] + 10^(2+ilog10(P[i+3])+ilog10(P[i+2]))*P[i+1] + 10^(3+ilog10(P[i+3])+ilog10(P[i+2])+ilog10(P[i+1]))*P[i], i=1..nops(P)-3)]); # Robert Israel, Apr 14 2016
CROSSREFS
KEYWORD
nonn,base
EXTENSIONS
Edited by Charles R Greathouse IV, Apr 23 2010
STATUS
approved