OFFSET
1,8
COMMENTS
Multiplicity of prime divisors of n, where n is a number composed of the reverse sorted digits of a prime number.
LINKS
Joshua Michael McAteer, Table of n, a(n) for n = 1..9592
EXAMPLE
The 28th prime number is 107. The reverse sorted digits are 710. The factorization of 710 is 2, 5, 71, therefore the 28th term in this sequence is 3.
PROG
(MATLAB)
nmax= 100;
p = primes(nmax);
lp = length(p);
lfac = zeros(1, lp);
for i = 1:lp
digp=str2double(regexp(num2str(p(i)), '\d', 'match'));
ldigp = flip(sort(digp));
l=length(digp);
conv = 10.^flip(0:(l-1));
lnum = sum(conv.*ldigp);
lfac(i) = numel(factor(lnum));
end
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Joshua Michael McAteer, Aug 06 2019
STATUS
approved