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a(n) is the closest number to n-th prime which is divisible by n.
8

%I #7 Aug 15 2017 20:38:57

%S 2,4,6,8,10,12,14,16,27,30,33,36,39,42,45,48,51,54,76,80,63,88,92,96,

%T 100,104,108,112,116,120,124,128,132,136,140,144,148,152,156,160,164,

%U 168,172,176,180,184,188,240,245,250,255,260,265,270,275,280,285,290

%N a(n) is the closest number to n-th prime which is divisible by n.

%F a(n)=n*floor[(floor(n/2)+p(n))/n], where p(n) is the n-th prime.

%e 24th prime, 89 is between 72 and 96, closer to 96, so a(24)=96;

%e 25th prime, 97 is between 75 and 100, closer to 100, so a(25)=100.

%t Table[n*Floor[(Floor[n/2]+Prime[n])/n], {n, 1, 100}]

%Y Cf. A082894-A082900.

%K nonn

%O 1,1

%A _Labos Elemer_, Apr 22 2003