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 A081430 Class 11- primes. 14
 1266767, 1520159, 2486717, 3316619, 4144541, 4512947, 4836779, 5389519, 5638379, 6218827, 6448979, 6633457, 6771419, 6907247, 7460149, 7462639, 7600597, 7739033, 7874627, 8153567, 8291573, 9110639, 9112319, 9121003 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 REFERENCES R. K. Guy, Unsolved Problems in Number Theory, A18. LINKS M. F. Hasler, Table of n, a(n) for n=1..1000 MATHEMATICA PrimeFactors[n_Integer] := Flatten[Table[ #[[1]], {1}] & /@ FactorInteger[n]]; f[n_Integer] := Block[{m = n}, If[m == 0, m = 1, While[ IntegerQ[m/2], m /= 2]; While[ IntegerQ[m/3], m /= 3]]; Apply[Times, PrimeFactors[m] - 1]]; ClassMinusNbr[n_] := Length[NestWhileList[f, n, UnsameQ, All]] - 3; Prime[ Select[ Range[300000, 1000000], ClassMinusNbr[ Prime[ # ]] == 1 &]] CROSSREFS Cf. A005113, A056637, A005109, A005110, A005111, A005112, A081424, A081425, A081426, A081427, A081429. Sequence in context: A090615 A222975 A180624 * A254026 A254019 A254893 Adjacent sequences: A081427 A081428 A081429 * A081431 A081432 A081433 KEYWORD nonn AUTHOR Robert G. Wilson v, Mar 20 2003 STATUS approved

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Last modified November 29 13:18 EST 2022. Contains 358430 sequences. (Running on oeis4.)