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A105299
Primes formed by concatenation of 8 consecutive triangular numbers.
0
105120136153171190210231, 351378406435465496528561, 8425584666850788549185905863208673687153, 649230650370651511652653653796654940656085657231
OFFSET
1,1
EXAMPLE
a(1)=105120136153171190210231 because 105120136153171190210231 is the prime formed by concatenation of 8 consecutive triangular numbers i.e. 105,120,136,153,171,190,210 and 231.
MATHEMATICA
Select[FromDigits[Flatten[IntegerDigits/@#]]& /@Partition[Accumulate[Range[2000]], 8, 1], PrimeQ] (* Harvey P. Dale, Mar 20 2011 *)
CROSSREFS
Sequence in context: A216854 A008916 A292859 * A340397 A094232 A234594
KEYWORD
base,nonn
AUTHOR
Shyam Sunder Gupta, Apr 25 2005
STATUS
approved