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A061802 Sum of n-th row of triangle of primes: 2; 2 3 2; 2 3 5 3 2; 2 3 5 7 5 3 2; ...; where n-th row contains 2n+1 terms. 3

%I

%S 2,7,15,27,45,69,99,135,177,229,289,357,435,519,609,709,821,941,1069,

%T 1207,1351,1503,1665,1837,2023,2221,2425,2635,2851,3073,3313,3571,

%U 3839,4115,4403,4703,5011,5331,5661,6001,6353,6713,7085,7469,7859,8255,8665

%N Sum of n-th row of triangle of primes: 2; 2 3 2; 2 3 5 3 2; 2 3 5 7 5 3 2; ...; where n-th row contains 2n+1 terms.

%C Row sums of A138143. - _Omar E. Pol_, Feb 13 2014

%H Harry J. Smith, <a href="/A061802/b061802.txt">Table of n, a(n) for n = 0..1000</a>

%F a(n) = a(n-1) + p(n) + p(n-1) where p(n) = n-th prime.

%F a(n) = A007504(n) + A007504(n+1) so we have the asymptotic expansion a(n) ~ n^2*log(n). - _Henry Bottomley_, May 30 2001

%o (PARI) { n=-1; a=q=0; forprime (p=2, prime(1001), write("b061802.txt", n++, " ", a+=p + q); q=p ) } \\ _Harry J. Smith_, Jul 28 2009

%K nonn,easy

%O 0,1

%A _Amarnath Murthy_, May 28 2001

%E More terms from Larry Reeves (larryr(AT)acm.org), May 29 2001

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Last modified May 21 02:55 EDT 2019. Contains 323434 sequences. (Running on oeis4.)