A174519 -id:A174519 - cp's OEIS frontend

A174520 Sum of all composite numbers in-between prime numbers p(n) and p(n+2).

4, 10, 33, 39, 57, 63, 81, 193, 160, 200, 287, 159, 177, 385, 530, 340, 380, 527, 279, 452, 623, 673, 1081, 948, 399, 417, 423, 441, 1893, 1947, 1057, 808, 1434, 1446, 920, 1570, 1295, 1345, 1730, 1060, 1854, 1866, 777, 783, 2453, 4642, 3062, 903, 921, 1873

Offset: 1

Vladimir Joseph Stephan Orlovsky, Mar 21 2010

nonn

2_3_4_5 -> 4, 3_4_5_6_7 -> 4+6=10, 5_6_7_8_9_10_11 -> 6+8+9+10=33, ..

Cf. A034962, A054265, A174518, A174519

f[n_,x_]:=n*x+x*(x+1)/2;Table[f[Prime[n],Prime[n+2]-Prime[n]-1]-Prime[n+1],{n,5!}]

A174521 Primes that are the sum of all composite numbers in-between prime numbers p(n) and p(n+2).

Original entry on oeis.org

193, 673, 1873, 2207, 2833, 4391, 3023, 8209, 5903, 8999, 6047, 9643, 7537, 19843, 10273, 29399, 11953, 12433, 20879, 35999, 36241, 23761, 23831, 24907, 20353, 32401, 33403, 22367, 34129, 57367, 49123, 74311, 51197, 40037, 42773, 71399

Offset: 1

Vladimir Joseph Stephan Orlovsky, Mar 21 2010

nonn

20+21+22+24+25+26+27+28=193,..

Harvey P. Dale, Table of n, a(n) for n = 1..2000

Cf. A034962, A054265, A174518, A174519, A174520

f[n_,x_]:=n*x+x*(x+1)/2;Select[Table[f[Prime[n],Prime[n+2]-Prime[n]-1]-Prime[n+1],{n,6!}],PrimeQ[ # ]&]
Select[Table[Total[Select[Range[Prime[n],Prime[n+2]],CompositeQ]],{n,1000}],PrimeQ] (* Harvey P. Dale, May 13 2017 *)

cp's OEIS Frontend

A174520 Sum of all composite numbers in-between prime numbers p(n) and p(n+2).

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