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.
11, 7, 5, 3, 2, 2063, 3253, 3251, 14293, 2442191, 2442179, 2442173, 2442151, 2442133, 2442113, 466343539, 793234063, 10158613657, 5200298339, 281201652541, 3140590111859, 1523243332991, 1631014452929, 1008266115029
Offset: 1
Examples
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.
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.
Crossrefs
Cf. A239790.
Programs
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UBASIC
10 P=1:KM=0:K=0:'puzzle 1290, Meller 20 P=nxtprm(P):if P>2^32-20 then end 30 gosub *SODP:if S=prmdiv(S) then K=K+1:Q=P:goto 20 40 if K>KM then print K, Q:KM=K 50 K=0:goto 20 200 *SODP:S=0:L=alen(P) 210 for I=1 to L:D=val(mid(str(P), I+1, 1)) 220 S=S+D:next I 230 return
Extensions
a(18)-a(24) from Giovanni Resta, Apr 09 2014
Comments