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A099756 For each single digit {0,1,...,9} record the smallest prime made up of copies of that digit (if there is one); repeat for all of the C(10,2) = 45 pairs of distinct decimal digits; then for all triples; etc. 7
11, 2, 3, 5, 7, 101, 211, 13, 41, 151, 61, 17, 181, 19, 23, 227, 29, 43, 53, 37, 83, 47, 499, 557, 59, 67, 787, 79, 89, 1021, 103, 401, 1051, 601, 107, 1801, 109, 2003, 2027, 2029, 4003, 503, 307, 3083, 4007, 409, 5077, 509, 607, 8087, 709, 809, 1123, 241, 251, 1621 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..56.

EXAMPLE

There are no primes that consist of copies of the digit 4, or 6, or 8, or 9, or {0,2}, or {0,3}, etc.

MATHEMATICA

<<DiscreteMath`Combinatorica` ta={{0}}; upps=PrimePi[{11, 787, 22259, 70879, 607889, 4456789, 40456789, 304456879, 1123465789, 10123457689}]; Do[ks1=KSubsets[{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}, hu]; Table[fla=1; Do[If[Equal[Union[IntegerDigits[Prime[n]]], Part[ks1, j]]&& Equal[fla, 1], ta=Append[ta, Prime[n]]; fla=0], {n, PrimePi[1+10^(hu-1)], Part[upps, hu]}], {j, 1, Length[ks1]}], {hu, 1, 3}]; ta=Delete[ta, 1] (Labos)

CROSSREFS

Inspired by A099651. Cf. A016112.

Cf. A099653, A099654.

Sequence in context: A109864 A231433 A240454 * A088277 A089744 A160137

Adjacent sequences:  A099753 A099754 A099755 * A099757 A099758 A099759

KEYWORD

base,nonn,easy,fini

AUTHOR

N. J. A. Sloane, Nov 11 2004

EXTENSIONS

More terms from Labos Elemer, Nov 15 2004

STATUS

approved

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Last modified October 1 00:54 EDT 2020. Contains 337440 sequences. (Running on oeis4.)