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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

Harvey P. Dale, Table of n, a(n) for n = 1..1000

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 A064588

Adjacent sequences:  A105291 A105292 A105293 * A105295 A105296 A105297

KEYWORD

base,nonn

AUTHOR

Shyam Sunder Gupta, Apr 25 2005

STATUS

approved

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Last modified September 27 21:12 EDT 2021. Contains 347698 sequences. (Running on oeis4.)