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A105297 Primes formed by concatenation of 6 consecutive triangular numbers. 1
136101521, 153171190210231253, 231253276300325351, 86190394699010351081, 185281872118915191101930619503, 193061950319701199002010020301, 225782279123005232202343623653, 385033878139060393403962139903 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
a(1)=136101521 because 136101521 is the prime formed by concatenation of 6 consecutive triangular numbers i.e. 1,3,6,10,15 and 21.
MATHEMATICA
Select[FromDigits[Flatten[IntegerDigits/@#]]&/@Partition[Accumulate[ Range[ 500]], 6, 1], PrimeQ] (* Harvey P. Dale, Aug 27 2019 *)
CROSSREFS
Sequence in context: A152960 A034590 A185888 * A298729 A203505 A342214
KEYWORD
base,nonn
AUTHOR
Shyam Sunder Gupta, Apr 25 2005
STATUS
approved

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Last modified March 28 20:05 EDT 2024. Contains 371254 sequences. (Running on oeis4.)