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A324289
a(n) = A276086(A283477(n)).
6
2, 3, 5, 25, 7, 49, 117649, 184877, 11, 121, 1771561, 143, 36226650889, 59797108943, 546826709, 299019449675770681, 13, 169, 4826809, 23298085122481, 8254129, 68130645548641, 17750592470222918406076697669, 406193515012381653451063, 8223741426987700773289, 1553319630709265128413587, 1977089672816762887718980502697827
OFFSET
0,1
COMMENTS
All primes are present, and furthermore, each subsequence starting at each n = 2^k is converging towards p^A283477(0), p^A283477(1), p^A283477(2), p^A283477(3), ..., where p = A000040(2+k). For example, for a(2^4) = a(16), the prime is A000040(2+4) = 13, and its powers 13^1, 13^2, 13^6 and 13^12 occur in successive positions from a(16) to a(19). See also comments in A324342.
FORMULA
a(n) = A276086(A283477(n)).
For n >= 0, a(2^n) = A000040(2+n).
A001221(a(n)) = A324341(n).
A001222(a(n)) = A324342(n).
PROG
(PARI)
A002110(n) = prod(i=1, n, prime(i));
A030308(n, k) = bittest(n, k);
A283477(n) = prod(i=0, #binary(n), if(0==A030308(n, i), 1, A030308(n, i)*A002110(1+i)));
A276086(n) = { my(i=0, m=1, pr=1, nextpr); while((n>0), i=i+1; nextpr = prime(i)*pr; if((n%nextpr), m*=(prime(i)^((n%nextpr)/pr)); n-=(n%nextpr)); pr=nextpr); m; };
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 23 2019
STATUS
approved