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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..18.

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

Adjacent sequences:  A068844 A068845 A068846 * A068848 A068849 A068850

KEYWORD

nonn,base

AUTHOR

Amarnath Murthy, Mar 10 2002

EXTENSIONS

More terms from Sascha Kurz, Mar 17 2002

STATUS

approved

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Last modified July 24 23:25 EDT 2021. Contains 346273 sequences. (Running on oeis4.)