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A081639
Class 11+ primes.
14
8524807, 18381361, 18575041, 19180817, 21312019, 31984321, 34099231, 40357021, 44206633, 44839273, 48499459, 51148847, 51444961, 51884467, 54144121, 57129613, 57780487, 58293601, 61378571, 65578901, 66786721, 66787873
OFFSET
1,1
REFERENCES
R. K. Guy, Unsolved Problems in Number Theory, A18.
LINKS
MAPLE
For Maple program see Mathar link in A005105.
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]]; ClassPlusNbr[n_] := Length[ NestWhileList[f, n, UnsameQ, All]] - 3; Prime[ Select[ Range[150000], ClassPlusNbr[ Prime[ # ]] == 11 &]]
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Mar 20 2003
STATUS
approved