A105304 Primes formed by reverse concatenation of 4 consecutive triangular numbers.

10631, 13612010591, 2926285027752701, 4656456044654371, 13530133661320313041, 29890296462940329161, 34980347163445334191, 40755404704018639903, 52650523265200351681, 52975526505232652003

Offset

1,1

Links

Table of n, a(n) for n=1..10.

Example

a(1)=10631 because 10631 is the prime formed by reverse concatenation of 4consecutive triangular numbers i.e. 1,3,6 and 10.

Mathematica

Select[FromDigits[Flatten[IntegerDigits/@#]]&/@Reverse/@Partition[ Accumulate[ Range[400]], 4, 1], PrimeQ] (* Harvey P. Dale, Oct 12 2017 *)

Crossrefs

Sequence in context: A110018 A249229 A376795 * A009421 A013817 A013904

Adjacent sequences: A105301 A105302 A105303 * A105305 A105306 A105307

Keyword

base,nonn

Author

Shyam Sunder Gupta, Apr 25 2005

Status

approved