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A052078
Smallest prime formed by concatenating n consecutive decreasing numbers, 0 if no such prime exists.
3
2, 43, 0, 10987, 76543, 0, 73727170696867, 4645444342414039, 0, 56555453525150494847, 219218217216215214213212211210209, 0, 25242322212019181716151413, 6059585756555453525150494847, 0
OFFSET
1,1
COMMENTS
Starting numbers in concatenations are given by A052080.
If n is divisible by 3, a(n)=0. - Harvey P. Dale, Jun 03 2019
MATHEMATICA
Table[Min[Select[FromDigits[Flatten[IntegerDigits[#]]]&/@ Partition[ Range[ 1000, 1, -1], n, 1], PrimeQ]], {n, 20}]/.\[Infinity]->0 (* Harvey P. Dale, Jun 03 2019 *)
CROSSREFS
KEYWORD
nonn,base,nice
AUTHOR
Patrick De Geest, Jan 15 2000
EXTENSIONS
Terms for n>6 calculated by Carlos Rivera and Felice Russo
STATUS
approved