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A048553
a(n+1) is next smallest prime beginning with a(n), initial prime is 11.
10
11, 113, 11311, 113111, 1131113, 11311133, 1131113353, 113111335313, 11311133531339, 113111335313399, 1131113353133993, 113111335313399321, 11311133531339932153, 1131113353133993215379, 113111335313399321537911
OFFSET
0,1
LINKS
MAPLE
f:= proc(n)
local p, d;
for d from 1 do
p:= nextprime(n*10^d);
if p < (n+1)*10^d then return p fi
od
end proc:
A[1]:= 11:
for n from 2 to 20 do A[n]:= f(A[n-1]) od:
seq(A[n], n=1..20); # Robert Israel, Aug 16 2015
MATHEMATICA
a = {11}; Do[k = 1; w = IntegerDigits[a[[n - 1]]];
While[CompositeQ@ FromDigits[Join[w, IntegerDigits@ k]], k += 2];
AppendTo[a, FromDigits[Join[w, IntegerDigits@ k]]], {n, 2, 15}]; a (* Michael De Vlieger, Sep 21 2015 *)
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, May 15 1999
STATUS
approved