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 A236431 Numbers n such that both prime(n)+n and prime(n)-n give a triangular number. 0
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 OFFSET 1,2 COMMENTS Intersection of A115882 and A115883. The corresponding primes are 2, 3673, 2955107. No more terms up to 10^12. - Giovanni Resta, Jan 26 2014 LINKS EXAMPLE prime(1) is 2, and both 2+1=3 and 2-1=1 are triangular. PROG (PARI) lista(nn) = {p = primes(nn); for (n=1, #p, pn = p[n]; if (ispolygonal(pn - n, 3) && ispolygonal(pn + n, 3), print1(n, ", ")); ); } CROSSREFS Cf. A115882, A115883. Sequence in context: A168118 A086030 A094647 * A118709 A296145 A283369 Adjacent sequences:  A236428 A236429 A236430 * A236432 A236433 A236434 KEYWORD nonn,bref,more AUTHOR Michel Marcus, Jan 25 2014 STATUS approved

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Last modified April 20 22:22 EDT 2019. Contains 322310 sequences. (Running on oeis4.)