cp's OEIS Frontend

A240598 The smallest first term of a sequence of exactly n consecutive prime numbers each of which has the property that its digit sum is prime.

%I A240598 #18 May 11 2014 11:33:32
%S A240598 11,7,5,3,2,2063,3253,3251,14293,2442191,2442179,2442173,2442151,
%T A240598 2442133,2442113,466343539,793234063,10158613657,5200298339,
%U A240598 281201652541,3140590111859,1523243332991,1631014452929,1008266115029
%N A240598 The smallest first term of a sequence of exactly n consecutive prime numbers each of which has the property that its digit sum is prime.
%C A240598 There is no requirement on the order of primes that arise as the digit sums.
%C A240598 a(25) > 2*10^13. - _Giovanni Resta_, Apr 09 2014
%e A240598 a(15) = 2442113 because each of the following fifteen consecutive primes {2442113, 24422133, 2442151, 2442173, 2442179, 2442191, 2442197, 2442199, 2442227, 2442263, 2442287, 2442289, 2442311, 2442353, 2442359} has a sum of digits producing another prime number and the smallest is 2442113.
%e A240598 a(17) = 793234063  because each of the following seventeen consecutive primes {793234063 793234067 793234111 793234139 793234153 793234171 793234177 793234193 793234207 793234243 793234261 793234289 793234333 793234357 793234391 793234427 793234441} has a sum of digits producing another prime number and the smallest is 793234063.
%o A240598 (UBASIC)
%o A240598    10   P=1:KM=0:K=0:'puzzle 1290, Meller
%o A240598    20   P=nxtprm(P):if P>2^32-20 then end
%o A240598    30   gosub *SODP:if S=prmdiv(S) then K=K+1:Q=P:goto 20
%o A240598    40   if K>KM then print K, Q:KM=K
%o A240598    50   K=0:goto 20
%o A240598   200   *SODP:S=0:L=alen(P)
%o A240598   210   for I=1 to L:D=val(mid(str(P), I+1, 1))
%o A240598   220   S=S+D:next I
%o A240598   230   return
%Y A240598 Cf. A239790.
%K A240598 nonn,more,base
%O A240598 1,1
%A A240598 _Carlos Rivera_, Apr 08 2014
%E A240598 a(18)-a(24) from _Giovanni Resta_, Apr 09 2014