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A081633 Class 5+ primes. +0
20
1021, 1321, 1381, 1459, 1877, 2467, 2503, 2657, 2707, 3253, 3313, 3547, 3701, 3733, 3907, 4561, 4817, 4937, 5441, 5443, 5527, 5693, 5839, 5861, 6037, 6131, 6211, 6217, 6277, 6361, 6373, 6569, 6653, 7057, 7243, 7591, 7753, 7817, 7883, 8101, 8123, 8221 (list; graph; listen)
OFFSET

1,1

REFERENCES

R. K. Guy, Unsolved Problems in Number Theory, A18.

MAPLE

For Maple program see Mathar link.

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[1040], ClassPlusNbr[ Prime[ # ]] == 5 &]]

CROSSREFS

Cf. A005113, A005105, A005106, A005107, A005108, A081634, A081635, A081636, A081637, A081638, A081639.

Sequence in context: A069791 A088290 A082059 this_sequence A020388 A031969 A038461

Adjacent sequences: A081630 A081631 A081632 this_sequence A081634 A081635 A081636

KEYWORD

nonn

AUTHOR

Robert G. Wilson v (rgwv(AT)rgwv.com), Mar 20 2003

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Last modified September 5 19:27 EDT 2008. Contains 143485 sequences.


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