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%I #2 Mar 30 2012 17:26:35
%S 19,37,59,109,127,149,239,307,419,691,1009,1049,1229,1319,2129,2309,
%T 2477,3119,4019,5009,6091,8093,8297,9199,10139,10799,11093,12007,
%U 12391,13499,14009,14489,15091,15497,18397,20297,20899,21799,22109,23599
%N Primes p such that sod(p)=2*sod(nextprime(p)).
%C sod(19)=10=2*sod(23)=2*5
%C sod(59)=14=2*sod(61)=2*7
%C sod(691)=16=2*sod(701)=2*8
%C sod(2477)=20=2*sod(2503)=2*10
%C sod(8297)=26=2*sod(8311)=2*13
%C sod(9199)=28=2*sod(9203)=2*14
%C sod(25799)=32=2*sod(25801)=2*16
%C sod(63997)=34=2*sod(64007)=2*17
%C sod(98999)=44=2*sod(99013)=2*22
%C sod(568999)=46=2*sod(569003)=2*23
%C sod(788999)=50=2*sod(789001)=2*25
%C sod(4779997)=52=2*sod(4780007)=2*26
%C sod(7979969)=56=2*sod(7980013)=2*28
%C sod(29899993)=58=2*sod(29900009)=2*29
%C sod(27989999)=62=2*sod(27990031)=2*31.
%H Zak Seidov, <a href="http://zak08.livejournal.com/22316.html">Sod(p)=2*sod(nextprime(p))</a>
%t Reap[Do[If[(t1=Total[IntegerDigits[(p1=Prime[n])]])==2*(t2=Total[IntegerDigits[(p2=Prime[n+1])]]), Sow[{p1,p2,t1,t2}]],{n,2000000}]][[2,1]]
%Y A007953 Digital sum (sum of digits, sod).
%K base,nonn
%O 1,1
%A _Zak Seidov_, Jun 24 2010
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