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A210110 Primes p such that 2p*(p+1) is the sum of 2 successive primes. 1
2, 3, 5, 7, 23, 29, 41, 59, 79, 89, 101, 131, 139, 151, 197, 229, 317, 337, 347, 389, 397, 421, 479, 631, 743, 761, 821, 829, 953, 977, 1033, 1193, 1279, 1451, 1697, 1747, 1787, 1789, 1879, 1997, 1999, 2017, 2099, 2213, 2237, 2347, 2411, 2477, 2579, 2621, 2663 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..1000

EXAMPLE

2 is in the sequence because 2*2*(2+1) = 5+7 = 12.

3 is in the sequence because 2*3*(3+1) = 11+13 = 24.

5 is in the sequence because 2*5*(5+1) = 29+31 = 60.

7 is in the sequence because 2*7*(7+1) = 53+59 = 112.

23 is in the sequence because 2*23*(23+1) = 547+557 = 1104.

MAPLE

a:= proc(n) option remember; local p, t;

      p:= `if`(n=1, 1, a(n-1));

      do p:= nextprime(p);

         t:= p*(p+1);

         if prevprime(t)+nextprime(t)=2*t then return p fi

      od

    end:

seq (a(n), n=1..60); # Alois P. Heinz, Mar 19 2012

CROSSREFS

Cf. A001043.

Sequence in context: A225659 A068690 A069556 * A235144 A235126 A309248

Adjacent sequences:  A210107 A210108 A210109 * A210111 A210112 A210113

KEYWORD

nonn

AUTHOR

Gerasimov Sergey, Mar 17 2012

STATUS

approved

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Last modified September 21 10:03 EDT 2020. Contains 337268 sequences. (Running on oeis4.)