A221867
Let m = A153022(n); a(n) = (1 + sum_{i=1..m} prime(i)^2)/(1+m).
Original entry on oeis.org
54, 218, 222054, 669806, 155593313228, 31860927184920, 37843679840313254, 5349233671440437948, 65075392901385088766, 102744428793110424984, 251471854505406311064463, 1074272348712875302655077, 1114427338015137279788981
Offset: 1
For n=2, m=10, a(2) = 2398/11=218.
Cf.
A007504,
A045345,
A171399,
A050247,
A050248,
A024450,
A111441,
A217599,
A217600,
A122140,
A223936,
A223937,
A024525,
A153022.
A158682
Numbers n such that 1 plus the sum of the first n primes is divisible by n+1.
Original entry on oeis.org
2, 6, 224, 486, 734, 50046, 142834, 170208, 249654, 316585342, 374788042, 2460457826, 2803329304, 6860334656, 65397031524, 78658228038
Offset: 1
-
k = 0; s = 1; p = 2; lst = {}; While[k < 10^9, s = s + p; If[ Mod[s, ++k + 1] == 0, AppendTo[lst, k]; Print[{k, p}]]; p = NextPrime@ p]
Showing 1-2 of 2 results.
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