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A116368 Central terms of the triangle in A116366. 2
6, 12, 20, 30, 42, 54, 62, 76, 90, 102, 116, 130, 144, 154, 166, 190, 200, 218, 234, 246, 260, 276, 288, 320, 330, 342, 358, 372, 384, 408, 424, 448, 456, 486, 500, 516, 536, 550, 570, 588, 602, 624, 636, 654, 662, 690, 714, 730, 750, 774, 796, 810, 828, 850, 864, 882, 890, 918, 928 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A000040(2n) + A000040(n+1).

a(n) = A116366(2*n-1, n).

EXAMPLE

For n=4, prime(2n) = prime(8) = 19, and prime(n+1) = prime(5) = 11, so a(4) = 19 + 11 = 30. - Michael B. Porter, Aug 15 2016

MATHEMATICA

Table[Prime[2n] + Prime[n+1], {n, 1, 70}](* Terry D. Grant, Aug 15 2016 *)

PROG

(PARI) vector(70, n, prime(2*n) + prime(n+1)) \\ G. C. Greubel, May 18 2019

(MAGMA) [NthPrime(2*n) + NthPrime(n+1): n in [1..70]]; // G. C. Greubel, May 18 2019

(Sage) [nth_prime(2*n) + nth_prime(n+1) for n in (1..70)] # G. C. Greubel, May 18 2019

(GAP) List([1..70], n-> Primes[2*n] + Primes[n+1]) # G. C. Greubel, May 18 2019

CROSSREFS

Sequence in context: A109895 A083209 A080714 * A290467 A007622 A180291

Adjacent sequences:  A116365 A116366 A116367 * A116369 A116370 A116371

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Feb 06 2006

STATUS

approved

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Last modified May 28 12:18 EDT 2020. Contains 334681 sequences. (Running on oeis4.)