A278139 Primes, starting with a(1)=2, whose successive differences are increasing triangular numbers.

2, 3, 13, 41, 107, 227, 503, 881, 1409, 2039, 2819, 3947, 5273, 6869, 8699, 11549, 15377, 19937, 24593, 30809, 38069, 47939, 58379, 69257, 82787, 98897, 115733, 133499, 152027, 172127, 192833, 218711, 247391, 279269, 315047, 355517, 399473, 444623

Offset

1,1

Links

Table of n, a(n) for n=1..38.

Mathematica

lst={1}; p[1]=2; p[n_]:=p[n]=Module[{i=Last[lst]+1},
While[!PrimeQ[p[n-1]+i*(i-1)/2], i++]; AppendTo[lst, i]; p[n-1]+i*(i-1)/2];
p/@Range[50]

Crossrefs

Cf. A088173, A275030.

Sequence in context: A264042 A122719 A106866 * A280005 A235626 A164133

Adjacent sequences: A278136 A278137 A278138 * A278140 A278141 A278142

Keyword

easy,nonn

Author

Ivan N. Ianakiev, Nov 13 2016

Status

approved