A105302 Primes formed by reverse concatenation of 6 consecutive triangular numbers.

665545362821, 496465435406378351, 946903861820780741, 112810811035990946903, 195318911830177017111653, 382837413655357034863403, 133661320313041128801272012561

Offset

1,1

Links

Harvey P. Dale, Table of n, a(n) for n = 1..2500

Example

a(1)=665545362821 because 665545362821 is the prime formed by reverse concatenation of 6 consecutive triangular numbers i.e. 21,28,36,45,55 and 66.

Mathematica

Select[FromDigits[Flatten[IntegerDigits/@Reverse[#]]]&/@Partition[Accumulate[ Range[ 200]], 6, 1], PrimeQ] (* Harvey P. Dale, May 06 2022 *)

Crossrefs

Sequence in context: A306891 A297006 A230559 * A015421 A335336 A180612

Adjacent sequences: A105299 A105300 A105301 * A105303 A105304 A105305

Keyword

base,nonn

Author

Shyam Sunder Gupta, Apr 25 2005

Status

approved