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A360188
Primes p such that the six consecutive primes starting at p are congruent to 1,2,4,5,7,8 (mod 9) in that order.
1
56197, 342037, 464941, 534637, 637327, 651169, 698239, 774919, 823789, 1142083, 1260757, 1382167, 1498789, 1614637, 1625707, 1814599, 1881811, 2213389, 2228509, 2597869, 2602783, 2821141, 2833309, 2980531, 3009043, 3019339, 3056959, 3083869, 3185551, 3204739, 3300139, 3593917, 3837727
OFFSET
1,1
LINKS
EXAMPLE
a(1) = 56197 since it is the least prime that is the first of six consecutive primes, {56197, 56207, 56209, 56237, 56239, 56249}, which are congruent to {1, 2, 4, 5, 7, 8} (mod 9).
217 is not a term because [217, 223, 227, 229, 233, 239] (mod 9) = [1, 7, 2, 4, 8, 5].
MATHEMATICA
p = 19; lst = {}; Do[ While[ !PrimeQ[p] || Mod[ NextPrime[p], 9] != 2 || Mod[NextPrime[p, 2], 9] != 4 || Mod[NextPrime[p, 3], 9] != 5 || Mod[NextPrime[p, 4], 9] != 7 || Mod[NextPrime[p, 5], 9] != 8, p += 18]; AppendTo [lst, p]; p += 18, {33}]; lst
CROSSREFS
Cf. A038194.
Sequence in context: A230336 A252320 A252020 * A031655 A203964 A198165
KEYWORD
nonn
AUTHOR
STATUS
approved