The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A084697

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A084697

a(1) = 2; for n >= 1, k>=1, a(n+1) = a(n) + k*n is the smallest such prime.
(history; published version)

#29 by Bruno Berselli at Fri Mar 18 05:43:32 EDT 2016

STATUS

proposed

approved

#28 by Zak Seidov at Fri Mar 18 02:42:45 EDT 2016

STATUS

editing

proposed

#27 by Zak Seidov at Fri Mar 18 02:42:24 EDT 2016

LINKS

Zak Seidov, <a href="/A084697/a084697.png">Graph of first differences of A084697.</a>

STATUS

approved

editing

#26 by N. J. A. Sloane at Mon Oct 26 22:45:06 EDT 2015

STATUS

proposed

approved

#25 by Robert Israel at Mon Oct 26 20:31:37 EDT 2015

STATUS

editing

proposed

#24 by Robert Israel at Mon Oct 26 20:31:32 EDT 2015

COMMENTS

Conjecture: a(n) ~ c n^2 log(n) for some positive constant c. - Robert Israel, Oct 26 2015

STATUS

proposed

editing

#23 by Robert Israel at Mon Oct 26 20:11:54 EDT 2015

STATUS

editing

proposed

#22 by Robert Israel at Mon Oct 26 20:11:50 EDT 2015

MAPLE

if n::odd then delta:= 2*n

else delta:= n

fi:

for q from a[n] + delta by delta while not isprime(q) do od:

a[n+1]:= q

STATUS

proposed

editing

#21 by Robert Israel at Mon Oct 26 20:10:45 EDT 2015

STATUS

editing

proposed

#20 by Robert Israel at Mon Oct 26 20:10:24 EDT 2015

MAPLE

a[1]:= 2: a[2]:= 3:

for n from 2 to 1000 do

if n::odd then delta:= 2*n

else delta:= n

fi:

for q from a[n] + delta by delta while not isprime(q) do od:

a[n+1]:= q

od:

seq(a[i], i=1..1000); # Robert Israel, Oct 26 2015

STATUS

approved

editing