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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.
2
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
1,1
COMMENTS
There is no requirement on the order of primes that arise as the digit sums.
a(25) > 2*10^13. - Giovanni Resta, Apr 09 2014
EXAMPLE
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.
PROG
(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
CROSSREFS
Cf. A239790.
Sequence in context: A236546 A155914 A087896 * A144262 A110093 A282345
KEYWORD
nonn,more,base
AUTHOR
Carlos Rivera, Apr 08 2014
EXTENSIONS
a(18)-a(24) from Giovanni Resta, Apr 09 2014
STATUS
approved