a(n) >= a(n-1) and sum of first n terms is prime

Robert G. Wilson v rgwv at kspaint.com
Thu Dec 19 18:17:57 CET 2002


Neil,

	Would it not be better to ask for the first number to appear exactly n time? 
i.e.; 2, 294, 12, 6, ...

Bob.

Neil Fernandez wrote:
> 2, 3, 6, 6, 6, 6, 8, 10, 12, 12, 12, 14, 16, 18, 18, 18, 24, 32, 34, 36,
> 38, 42, 46, 48, 54, 56, 64, 68, 78, 90, 90, 94, 102, 114, 122, 124, 134,
> 144, 148, 150, 152, 160, 168, 170, 178, 182, 190, 192, 200, 216, 220,
> 222, 234, 234, 234, 246, 260, 264, 268, 270, 278, 280, 290, 292, 294,
> 294, 300, 302, 310, 312, 312, 318, 318, 330, 348, 350, 370, 380, 384,
> 388, 408, 410, 424, 428, 444, 450, 450
> 
> a(n) = smallest integer greater or equal to a(n-1) such that the sum of
> the first n terms is prime
> 
> First numbers to appear once, twice, three times, etc. are 2, 6, 6, 6, ?
> 
> (See also Felice Russo's sequence A051935, where a(n) must be strictly
> greater than a(n-1)).
> 
> Neil







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