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%I #19 Jan 22 2024 15:14:48
%S 2,23,29,41,43,47,61,67,83,89,181,263,269,281,283,461,463,467,487,661,
%T 683,863,881,883,887,1889,2683,2687,2689,2861,2887,4861,4889,6689,
%U 6863,6869,6883,8681,8689,8861,8863,8867,8887,26881
%N a(1)=2, a(n+1) is the smallest prime with sum of even digits >= sum of even digits of a(n).
%C An increasing sequence of primes a(n) such that the sequence A071648(a(n)) is nondecreasing. - _R. J. Mathar_, May 15 2010
%H Harvey P. Dale, <a href="/A156614/b156614.txt">Table of n, a(n) for n = 1..100</a>
%e 2, 23(2=2), 29(2=2), 41(4>2), 43(4=4), 61(6>4), 67(6=6), 83(8>6), 89(8=8), 181(8=8), 263(2+6=8), 269(2+6=2+6), 281(2+8>2+6), 283(2+8=2+8), 461(4+6=2+8), etc.
%t t={}; max=0; Do[p=Prime[i]; If[(x=Total[Select[IntegerDigits[p],EvenQ[#] &]])>=max, max = x; AppendTo[t,p]],{i,3000}]; t (* _Jayanta Basu_, May 22 2013 *)
%t sped[p_]:=Module[{d1=Total[Select[IntegerDigits[p],EvenQ]],p2=NextPrime[p]},While[ Total[ Select[ IntegerDigits[ p2],EvenQ]]<d1,p2=NextPrime[p2]];p2]; NestList[sped,2,50] (* or *) DeleteDuplicates[Table[{p,Total[Select[IntegerDigits[p],EvenQ]]},{p,Prime[Range[ 3000]]}],Greater[ #1[[2]],#2[[2]]]&][[;;,1]](* _Harvey P. Dale_, Jan 22 2024 *)
%Y Cf. A000040.
%K nonn,base,less
%O 1,1
%A _Juri-Stepan Gerasimov_, Feb 11 2009
%E Corrected (4861 inserted) by _R. J. Mathar_, May 15 2010
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