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A037055 Smallest prime containing exactly n 1's. 16
13, 11, 1117, 10111, 101111, 1111151, 11110111, 101111111, 1111111121, 11111111113, 101111111111, 1111111118111, 11111111111411, 111111111116111, 1111111111111181, 11111111101111111, 101111111111111111 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Except for the initial term, A037055 is conjectured to be identical to A084673. - Robert G. Wilson v, Jul 04 2003

LINKS

Table of n, a(n) for n=1..17.

MATHEMATICA

f[n_, b_] := Block[{k = 10^(n + 1), p = Permutations[ Join[ Table[b, {i, 1, n}], {x}]], c = Complement[Table[j, {j, 0, 9}], {b}], q = {}}, Do[q = Append[q, Replace[p, x -> c[[i]], 2]], {i, 1, 9}]; r = Min[ Select[ FromDigits /@ Flatten[q, 1], PrimeQ[ # ] & ]]; If[r ? Infinity, r, p = Permutations[ Join[ Table[ b, {i, 1, n}], {x, y}]]; q = {}; Do[q = Append[q, Replace[p, {x -> c[[i]], y -> c[[j]]}, 2]], {i, 1, 9}, {j, 1, 9}]; Min[ Select[ FromDigits /@ Flatten[q, 1], PrimeQ[ # ] & ]]]]; Table[ f[n, 1], {n, 1, 18}]

CROSSREFS

Cf. A084673, A065584, A065821, A037054, A034388, A036507-A036536.

Cf. A037053, A037057, A037059, A037061, A037063, A037065, A037067, A037069, A037071.

Sequence in context: A083229 A140554 A002591 * A022969 A023455 A055124

Adjacent sequences:  A037052 A037053 A037054 * A037056 A037057 A037058

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, Jan 04 1999.

EXTENSIONS

More terms from Sascha Kurz, Feb 10 2003

Edited by Robert G. Wilson v, Jul 04 2003

STATUS

approved

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Last modified November 25 15:47 EST 2014. Contains 249998 sequences.