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Search: id:A056938
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| A056938 |
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Concatenate all the prime divisors in previous term, starting at 49. |
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+0
7
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| 49, 77, 711, 3379, 31109, 132393, 344131, 1731653, 71143523, 11115771019, 31135742029, 717261644891, 11193431873899, 116134799345907, 3204751189066719, 31068250396355573, 62161149980213343
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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This is the search for the home prime for 49.
This sequence has now been followed for 100 steps without a prime being reached (after which of course it would simply repeat).
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LINKS
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N. J. A. Sloane, Table of n, a(n) for n = 1..100 [taken from Patrick De Geest's web page]
P. De Geest, Home Primes
N. J. A. Sloane, Factorization of a(n) for n = 1..100 [taken from Patrick De Geest's web page]
Eric Weisstein's World of Mathematics, Home Prime
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MATHEMATICA
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g[n_] := (x = n; d = {}; While[FactorInteger[x] != {}, f = FactorInteger[x, FactorComplete -> True][[1, 1]]; x = x/f; AppendTo[d, IntegerDigits[f]]]; FromDigits[Flatten[d]]); NestList[g, 49, 25]
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PROGRAM
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(PARI) a=vector(35); a[1]=49; for(k=2, length(a), f=factor(a[k-1]); for(i=1, matsize(f)[1], l=10^ceil(log(f[i, 1])/log(10)); for(j=1, f[i, 2], a[k]=a[k]*l+f[i, 1]))) - M. F. Hasler (Maximilian.Hasler(AT)gmail.com), Mar 09 2007
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CROSSREFS
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Cf. A006919, A037273, A037274, A037271.
Sequence in context: A063163 A103216 A036307 this_sequence A106311 A006832 A093894
Adjacent sequences: A056935 A056936 A056937 this_sequence A056939 A056940 A056941
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KEYWORD
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nonn,base
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AUTHOR
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Robert G. Wilson v (rgwv(AT)rgwv.com), Sep 05 2000
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