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A068842 Smallest prime larger than 2^n whose digits begin with those of 2^n. 1
11, 23, 41, 83, 163, 3203, 641, 1283, 25601, 51203, 10243, 20483, 40961, 81929, 163841, 327689, 6553621, 1310723, 2621447, 5242883, 10485767, 20971529, 41943049, 838860817, 167772161, 335544323, 6710886407, 1342177283 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,1
LINKS
EXAMPLE
a(5) = 3203 with leading digits 32 = 2^5.
MATHEMATICA
f[n_] := For[x=10, True, x*=10, For[y=0, y<x, y++, If[PrimeQ[x*n+y], Return[x*n+y]]]]; a[n_] := f[2^n]
CROSSREFS
Cf. A068841.
Sequence in context: A052034 A077041 A190797 * A357364 A199848 A352494
KEYWORD
nonn,base
AUTHOR
Amarnath Murthy, Mar 10 2002
EXTENSIONS
Edited by Dean Hickerson, Jun 09 2002
STATUS
approved

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Last modified May 26 07:52 EDT 2024. Contains 372807 sequences. (Running on oeis4.)