login
A324579
Numbers n for which n*A276086(n) is a product of primorial numbers (is a term of A025487).
4
1, 2, 4, 6, 8, 16, 30, 36, 40, 72, 210, 240, 252, 256, 2310, 2520, 2560, 2592, 2808, 5184, 30030, 32832, 510510, 573300, 9699690, 223092870, 232792560
OFFSET
1,2
COMMENTS
Sequence is infinite because each primorial number (A002110) is present.
PROG
(PARI)
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; };
A324580(n) = n*A276086(n);
A322585(n) = { my(f = factor(n)); for(i=1, #f~, if((primepi(f[i, 1])!=i)||((i>1)&&(f[i-1, 2]<f[i, 2])), return(0))); (1); };
isA324579(n) = A322585(A324580(n));
CROSSREFS
Subsequence of A324578.
Cf. A002110 (a subsequence), A025487, A276086, A324580, A322585.
Sequence in context: A317087 A100778 A368325 * A271520 A122408 A326037
KEYWORD
nonn,more
AUTHOR
Antti Karttunen, Mar 09 2019
STATUS
approved