login
A068847
Smallest prime with same leading digits as 7^n.
2
11, 71, 491, 3433, 24019, 168071, 11764967, 8235431, 576480103, 403536071, 2824752493, 19773267431, 1384128720101, 9688901040727, 6782230728491, 474756150994337, 3323293056960127, 23263051398720713, 162841359791044903
OFFSET
0,1
EXAMPLE
a(3)=3433 because this is the smallest prime starting with 7^3=343.
MAPLE
for i from 0 to 30 do a := nextprime(7^i*10); b := 1; while(a-7^i*10^b>=10^b) do b := b+1; a := nextprime(7^i*10^b); end do; c[i] := a; end do:q := seq(c[i], i=0..30);
CROSSREFS
Cf. A068846.
Sequence in context: A300541 A123362 A199488 * A139185 A103998 A160587
KEYWORD
nonn,base
AUTHOR
Amarnath Murthy, Mar 10 2002
EXTENSIONS
More terms from Sascha Kurz, Mar 17 2002
STATUS
approved