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A275030 a(1) = 2. a(n) is the smallest prime such that a(n) - a(n-1) is a triangular number. 1
2, 3, 13, 19, 29, 107, 113, 149, 227, 233, 239, 317, 353, 359, 479, 557, 563, 569, 647, 653, 659, 1187, 1193, 1229, 1307, 1373, 1409, 1487, 1493, 1499, 1619, 1697, 1733, 1811, 1847, 1913, 1949, 2027, 2063, 2069, 2447, 2657, 2663, 2699, 2777, 2843, 2879, 2957, 2963 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..49.

MATHEMATICA

triQ[n_]:=IntegerQ[Sqrt[8n+1]];

NestList[(x=NextPrime[#]; While[!triQ[x-#], x=NextPrime[x]]; x)&, 2, 100]

PROG

(PARI) lista(nn) = {print1(p = 2, ", "); for (n=2, nn, q = nextprime(p+1); while (! ispolygonal(q-p, 3), q = nextprime(q+1)); print1(q, ", "); p = q; ); } \\ Michel Marcus, Nov 13 2016

CROSSREFS

Cf. A278139.

Sequence in context: A143871 A225517 A254462 * A194598 A080359 A193507

Adjacent sequences:  A275027 A275028 A275029 * A275031 A275032 A275033

KEYWORD

easy,nonn

AUTHOR

Ivan N. Ianakiev, Nov 13 2016

STATUS

approved

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Last modified June 24 07:56 EDT 2021. Contains 345416 sequences. (Running on oeis4.)