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A190819
Initial primes of 7 consecutive primes with consecutive gaps 2, 4, 6, 8, 10, 12.
12
128981, 665111, 2798921, 3992201, 5071667, 5093507, 5344247, 10732817, 11920367, 16197947, 16462541, 16655447, 16943471, 21456047, 25793897, 32634311, 34051007, 34864211, 35250431, 38585201, 39898757, 49584371, 50375861, 51867197, 54738767, 55793951
OFFSET
1,1
COMMENTS
Subsequence of A190817, a(1) = 128981 = A190817(6).
a(n) + 42 is the greatest term in the sequence of 7 consecutive primes with 6 consecutive gaps 2, 4, 6, 8, 10, 12. - Muniru A Asiru, Aug 10 2017
EXAMPLE
Prime(12073..12079) = {128981, 128983, 128987, 128993, 129001, 129011, 129023} with first differences {2, 4, 6, 8, 10, 12}.
MAPLE
N:=10^7: # to get all terms <= N.
Primes:=select(isprime, [seq(i, i=3..N+42, 2)]):
Primes[select(t->[Primes[t+1]-Primes[t], Primes[t+2]-Primes[t+1],
Primes[t+3]-Primes[t+2], Primes[t+4]-Primes[t+3], Primes[t+5]-Primes[t+4], Primes[t+6]-Primes[t+5] ]=[2, 4, 6, 8, 10, 12], [$1..nops(Primes)-6])]; # Muniru A Asiru, Aug 04 2017
MATHEMATICA
d = Differences[Prime[Range[1000000]]]; Prime[Flatten[Position[Partition[d, 6, 1], {2, 4, 6, 8, 10, 12}]]] (* T. D. Noe, May 23 2011 *)
Prime[SequencePosition[Differences[Prime[Range[34*10^5]]], {2, 4, 6, 8, 10, 12}][[All, 1]]] (* Harvey P. Dale, Feb 18 2022 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Zak Seidov, May 21 2011
EXTENSIONS
Additional cross references from Harvey P. Dale, May 10 2014
STATUS
approved