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A142728
Nonprimes of the form (p(n)-2*n)/3, where p(n)=n-th prime.
1
0, 1, 1, 35, 35, 39, 45, 45, 49, 75, 77, 81, 95, 105, 115, 119, 143, 145, 147, 159, 187, 187, 207, 217, 219, 235, 235, 243, 249, 267, 273, 289, 321, 325, 335, 339, 361, 365, 369, 369, 381, 381, 395, 395, 411, 411, 417, 427, 441, 459, 465, 471, 471, 485, 485
OFFSET
1,4
LINKS
EXAMPLE
If n=1, then (p(1)-2*1)/3=(2-2)/3=0=a(1).
If n=7, then (p(7)-2*7)/3=(17-14)/3=1=a(2).
If n=8, then (p(8)-2*8)/3=(19-16)/3=1=a(3).
If n=43, then (p(43)-2*43)/3=(191-86)/3=35=a(4), etc.
MATHEMATICA
Select[Table[(Prime[n]-2n)/3, {n, 0, 500}], IntegerQ[#]&&!PrimeQ[#]&] (* Harvey P. Dale, Oct 18 2023 *)
CROSSREFS
Sequence in context: A307509 A291654 A257948 * A316111 A316348 A146205
KEYWORD
nonn
AUTHOR
EXTENSIONS
Corrected (29 replaced by double-35, 39 and 45, 115 inserted, 145 inserted, 338 replaced by 339 etc.) - R. J. Mathar, Apr 18 2010
STATUS
approved