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A240598
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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.
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2
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11, 7, 5, 3, 2, 2063, 3253, 3251, 14293, 2442191, 2442179, 2442173, 2442151, 2442133, 2442113, 466343539, 793234063, 10158613657, 5200298339, 281201652541, 3140590111859, 1523243332991, 1631014452929, 1008266115029
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OFFSET
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1,1
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COMMENTS
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There is no requirement on the order of primes that arise as the digit sums.
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LINKS
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EXAMPLE
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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.
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PROG
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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
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CROSSREFS
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KEYWORD
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nonn,more,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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