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A038345
Sum of the next n members of the list of twin primes.
0
3, 12, 41, 120, 307, 696, 1241, 1956, 3307, 5544, 8381, 12042, 16237, 21492, 27677, 33906, 42733, 54180, 65057, 76740, 88771, 104112, 124229, 146490, 169933, 196884, 230807, 263790, 297475, 339372, 385349, 441900, 496375, 557628, 617357, 672510, 743917, 807888
OFFSET
1,1
COMMENTS
Observation: a(26) is also equal to A000521(1) = 196884. - Omar E. Pol, Nov 29 2014
EXAMPLE
a(1) = 3, a(2) = 5+7 = 12, a(3) = 11+13+17 = 41, ...
a(26) = 7211+7213+7307+7309+7331+7333+7349+7351+7457+7459+7487+7489+7547+7549+7559+ 7561+7589+7591+7757+7759+7877+7879+7949+7951+8009+8011 = 196884. - Omar E. Pol, Nov 29 2014
MATHEMATICA
With[{nn=100}, Total/@TakeList[Union[Flatten[Select[ Partition[Prime[ Range[ 300nn]], 2, 1], #[[2]]-#[[1]]==2&]]], Range[nn]]] (* Requires Mathematica version 11 or later *) (* Harvey P. Dale, Apr 27 2018 *)
PROG
(PARI) isA001097(n) = (isprime(n) && (isprime(n+2) || isprime(n-2))) ;
lista(nn) = {v = select(x->isA001097(x), vector(nn, i, i)); idep = 1; for (n=1, sqrtint(#v), print1(sum(i=idep, idep+n-1, v[i]), ", "); idep += n; ); } \\ Michel Marcus, Nov 29 2014
CROSSREFS
Cf. A001097 (twin primes), A007468 (sum of next n primes), A000521.
Sequence in context: A126725 A053043 A263102 * A336337 A127120 A325482
KEYWORD
easy,nonn
AUTHOR
Den Roussel (DenRoussel(AT)webtv.net)
EXTENSIONS
More terms from Michel Marcus, Nov 29 2014
STATUS
approved