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A105294 Primes formed by concatenation of 3 consecutive triangular numbers. 1
210231253, 496528561, 630666703, 780820861, 99010351081, 495050505151, 918093169453, 9730987010011, 120901224612403, 135301369513861, 201002030120503, 223662257822791, 368563712837401, 379503822638503 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
a(1)=210231253 because 210231253 is the prime formed by concatenation of 3 consecutive triangular numbers i.e. 210,231 and 253.
MATHEMATICA
Select[FromDigits[Flatten[IntegerDigits[#]]]&/@Partition[Accumulate[ Range[300]], 3, 1], PrimeQ] (* Harvey P. Dale, Sep 29 2011 *)
CROSSREFS
Sequence in context: A187440 A092379 A233614 * A288079 A037253 A359129
KEYWORD
base,nonn
AUTHOR
Shyam Sunder Gupta, Apr 25 2005
STATUS
approved

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Last modified April 24 20:08 EDT 2024. Contains 371963 sequences. (Running on oeis4.)