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 A263676 Numbers that are both interprime and oblong. 2
 6, 12, 30, 42, 56, 72, 240, 342, 420, 462, 506, 552, 600, 650, 870, 1056, 1190, 1482, 1722, 1806, 2550, 2652, 2970, 3540, 4422, 6320, 7140, 8010, 10302, 12656, 13572, 14042, 17292, 18360, 19182, 19460, 20022, 22952, 23562, 24180, 27060, 29070, 29756, 31152, 33306, 35156, 35532, 39006 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Intersection of A024675 and A002378. - Omar E. Pol, Oct 24 2015 Lesser of consecutive primes is in the sequence A242383. LINKS Eric Weisstein's World of Mathematics, Interprime Eric Weisstein's World of Mathematics, Pronic Number EXAMPLE 342 is in this sequence because 342 = 18*19 is oblong, and 342 = (337 + 347)/2, with 337 and 347 consecutive primes. MATHEMATICA lim = 40000; Intersection[Plus @@@ Partition[Table[Prime@ n, {n, 2, PrimePi@ lim}], 2, 1]/2, Table[n (n + 1), {n, 0, lim}]] (* Michael De Vlieger, Nov 18 2015, after Clark Kimberling at A024675 and Robert G. Wilson v at A002378 *) PROG (PARI) {for(i=1, 500, n=i*(i+1); if(n==(precprime(n-1)+nextprime(n+1))/2, print1(n, ", ")))} CROSSREFS Cf. A002378, A024675, A075190, A075277, A075296, A078443, A130178, A242383, A263674, A263675. Sequence in context: A143272 A153877 A229491 * A083494 A126857 A161348 Adjacent sequences:  A263673 A263674 A263675 * A263677 A263678 A263679 KEYWORD nonn,easy AUTHOR Antonio Roldán, Oct 23 2015 STATUS approved

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Last modified October 21 08:47 EDT 2019. Contains 328292 sequences. (Running on oeis4.)