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 A100026 Consider all (2n+1)-digit palindromic primes of the form 10...0M0...01 (so that M is a palindrome with <= 2n-1 digits); a(n) = smallest such M. 7

%I

%S 0,3,3,3,5,8,323,5,8,212,3,161,8,3,242,3,8,10901,737,161,242,333,282,

%T 6,252,474,5,12921,8,131,18381,6,444,6,797,606,717,15351,464,333,626,

%U 545,13031,161,747,191,323,636,32523,303,282,888,686,18981,111,15951,12021

%N Consider all (2n+1)-digit palindromic primes of the form 10...0M0...01 (so that M is a palindrome with <= 2n-1 digits); a(n) = smallest such M.

%t f[n_] := Block[{k = 0, t = Flatten[Join[{1}, Table[0, {n - 1}]]]}, While[s = Drop[t, Min[ -Floor[ Log[10, k]/2], 0]]; k != FromDigits[ Reverse[ IntegerDigits[k]]] || !PrimeQ[ FromDigits[ Join[s, IntegerDigits[k], Reverse[s]]]], k++ ]; k]; Table[ f[n], {n, 56}] (from Robert G. Wilson v Nov 22 2004)

%Y The corresponding palindromic primes are shown in A100027.

%Y Cf. A099744, A099746, A100028.

%K nonn,base

%O 1,2

%A Harvey Dubner (harvey(AT)dubner.com), Nov 20 2004

%E More terms from _Robert G. Wilson v_, Nov 22 2004

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