OFFSET
1,2
EXAMPLE
1485 is a term as 1485 and 4851 both are triangular numbers.
MATHEMATICA
Do[k = FromDigits[ RotateLeft[ IntegerDigits[n(n + 1)/2]]]; l = Floor[ Sqrt[2k]]; If[k == l(l + 1)/2, Print[n(n + 1)/2]], {n, 1, 10^5}]
msdmeQ[n_]:=IntegerQ[(Sqrt[1+8*FromDigits[RotateLeft[IntegerDigits[ n]]]]-1)/2]; Select[Accumulate[Range[55900]], msdmeQ] (* Harvey P. Dale, Aug 22 2014 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Feb 22 2002
EXTENSIONS
Edited by Robert G. Wilson v, Feb 28 2002
Offset changed by Andrew Howroyd, Sep 17 2024
STATUS
approved