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 A241525 a(n) is the smallest start of a run of exactly n consecutive primes such that the sum of the digits of each prime is composite. 0
 19, 17, 13, 521, 509, 503, 499, 491, 14153, 25793, 25771, 37663, 37657, 98729, 98717, 98713, 98711, 98689, 98669, 98663, 98641, 98639, 98627, 98621, 98597, 98573, 69794393, 69794383, 268684679, 268684651, 268684627, 329788829, 545497787, 545497769, 545497759, 545497753, 545497747, 545497741, 545497727, 545497723, 545497691, 545497681, 545497679, 545497637, 545497633, 545497609 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS No more terms below 2^32 LINKS EXAMPLE a(3)=13 because the run of the 3 consecutive primes {13, 17, 19} is such that the sum of digits for each prime is {4, 8, 10}. 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. A240598. Sequence in context: A135734 A215021 A215085 * A321332 A109410 A230339 Adjacent sequences:  A241522 A241523 A241524 * A241526 A241527 A241528 KEYWORD nonn,base AUTHOR Carlos Rivera, Apr 24 2014 STATUS approved

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Last modified June 16 04:56 EDT 2021. Contains 345056 sequences. (Running on oeis4.)