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A081638 Class 10+ primes. 10
1065601, 2424973, 5114881, 7222561, 8124481, 8524091, 8647411, 8650321, 9190681, 9287521, 9590417, 10617601, 10929817, 11996161, 12349093, 12508081, 12786181, 12971117, 13570681, 14113027, 14308123, 14312743, 14476807 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

REFERENCES

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

LINKS

Table of n, a(n) for n=1..23.

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[ # ]] == 10 &]]

CROSSREFS

Cf. A005113, A005105, A005106, A005107, A005108, A081633, A081634, A081635, A081636, A081637, A081639.

Sequence in context: A076247 A076248 A234776 * A193054 A160687 A070042

Adjacent sequences:  A081635 A081636 A081637 * A081639 A081640 A081641

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Mar 20 2003

STATUS

approved

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Last modified May 25 12:30 EDT 2019. Contains 323568 sequences. (Running on oeis4.)