|
| |
|
|
A056938
|
|
Concatenate all the prime divisors in previous term, starting at 49.
|
|
7
| |
|
|
49, 77, 711, 3379, 31109, 132393, 344131, 1731653, 71143523, 11115771019, 31135742029, 717261644891, 11193431873899, 116134799345907, 3204751189066719, 31068250396355573, 62161149980213343
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
COMMENTS
| 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).
|
|
|
LINKS
| 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
|
|
|
MATHEMATICA
| 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]
|
|
|
PROG
| (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
|
|
|
CROSSREFS
| Cf. A006919, A037273, A037274, A037271.
Sequence in context: A063163 A103216 A036307 * A106311 A006832 A093894
Adjacent sequences: A056935 A056936 A056937 * A056939 A056940 A056941
|
|
|
KEYWORD
| nonn,base
|
|
|
AUTHOR
| Robert G. Wilson v (rgwv(AT)rgwv.com), Sep 05 2000
|
| |
|
|
