login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A306192
a(n) = (n - 1)*prime(n + 1).
4
0, 5, 14, 33, 52, 85, 114, 161, 232, 279, 370, 451, 516, 611, 742, 885, 976, 1139, 1278, 1387, 1580, 1743, 1958, 2231, 2424, 2575, 2782, 2943, 3164, 3683, 3930, 4247, 4448, 4917, 5134, 5495, 5868, 6179, 6574, 6981, 7240, 7831, 8106, 8471, 8756, 9495, 10258
OFFSET
1,2
COMMENTS
For n > 1, a(n) is the subdiagonal sum of the matrix M(n) whose determinant is A318173(n).
LINKS
FORMULA
a(n) = A033286(n + 1) - 2*A000040(n + 1).
a(n) = (n - 1)/(n + 1)*A033286(n + 1).
MAPLE
a := n -> (n-1)*ithprime(n+1): seq(a(n), n = 1 .. 100);
MATHEMATICA
a[n_]:=(n-1)*Prime[n+1]; Array[a, 100]
PROG
(Magma) [(n-1)*NthPrime(n+1): n in [1..100]];
(PARI) a(n) = (n-1)*prime(n+1);
(Python)
from sympy import prime
[(n-1)*prime(n+1) for n in range(1, 100)]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Stefano Spezia, Jan 28 2019
STATUS
approved