OFFSET
1,1
EXAMPLE
The prime corresponding to the triangular number 21 is 43.
MATHEMATICA
sm1[n_]:=Module[{p=NextPrime[n]}, While[Mod[p, n]!=1, p=NextPrime[p]]; p]; Join[ {2}, Table[sm1[(n(n+1))/2], {n, 2, 50}]] (* Harvey P. Dale, May 29 2020 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Sep 09 2003
EXTENSIONS
More terms from Sam Alexander, Dec 28 2003
STATUS
approved