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A141101
a(n) = prime(2*n) - 2*n.
1
1, 3, 7, 11, 19, 25, 29, 37, 43, 51, 57, 65, 75, 79, 83, 99, 105, 115, 125, 133, 139, 149, 153, 175, 179, 187, 197, 207, 213, 221, 231, 247, 251, 269, 279, 287, 299, 307, 319, 329, 339, 349, 357, 369, 373, 387, 397, 407, 423, 441, 455, 465, 471, 485, 491, 501
OFFSET
1,2
FORMULA
a(n) = A031215(n) - A005843(n). - Michel Marcus, Feb 01 2019 [Corrected by Georg Fischer, Dec 13 2022]
a(n) = A014689(A005843(n)). - Michel Marcus, Dec 13 2022
EXAMPLE
a(1) = prime(2*1) - 1*2 = prime(2) - 2 = 3 - 2 = 1.
a(4) = prime(2*4) - 4*2 = prime(8) - 8 = 19 - 8 = 11.
MAPLE
p:= ithprime: a:= seq(p(2*n)-2*n, n=1..100); # D. S. McNeil, Mar 21 2009
PROG
(PARI) a(n) = prime(2*n) - 2*n; \\ Michel Marcus, Dec 13 2022
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
a(32), a(40) corrected and extended by D. S. McNeil, Mar 21 2009
STATUS
approved