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A284573
Odd bisection of A278243: a(n) = A046523(A277324(n)).
2
2, 6, 12, 30, 60, 120, 180, 210, 420, 1080, 2160, 2520, 2520, 7560, 6300, 2310, 4620, 37800, 90720, 75600, 226800, 544320, 453600, 138600, 138600, 756000, 2268000, 831600, 415800, 2079000, 485100, 30030, 60060, 2910600, 24948000, 12474000, 49896000, 272160000, 136080000, 29106000, 87318000, 1360800000, 3265920000, 1496880000, 748440000
OFFSET
0,1
LINKS
FORMULA
a(n) = A046523(A277324(n)).
a(n) = A278243((2*n)+1).
PROG
(PARI)
A003961(n) = my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); \\ From Michel Marcus
A260443(n) = if(n<2, n+1, if(n%2, A260443(n\2)*A260443(n\2+1), A003961(A260443(n\2)))); \\ Cf. Charles R Greathouse IV's code for "ps" in A186891 and A277013.
A277324(n) = A260443((2*n)+1);
A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); }; \\ From Charles R Greathouse IV, Aug 17 2011
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Apr 11 2017
STATUS
approved