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A289622
Compound filter (prime signature & Carmichael's lambda): a(n) = P(A046523(n), A002322(n)), where P(n,k) is sequence A000027 used as a pairing function.
2
1, 3, 5, 14, 12, 27, 23, 44, 40, 42, 57, 90, 80, 61, 42, 187, 138, 148, 173, 117, 61, 111, 255, 324, 257, 142, 308, 148, 408, 558, 467, 773, 111, 216, 142, 856, 668, 259, 142, 375, 822, 625, 905, 222, 265, 357, 1083, 1323, 994, 477, 216, 265, 1380, 844, 306, 430, 259, 534, 1713, 2013, 1832, 601, 148, 3145, 142, 771, 2213, 363, 357
OFFSET
1,2
LINKS
FORMULA
a(n) = (1/2)*(2 + ((A046523(n)+A002322(n))^2) - A046523(n) - 3*A002322(n)).
PROG
(PARI)
A002322(n) = lcm(znstar(n)[2]); \\ This function from Charles R Greathouse IV, Aug 04 2012
A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); }; \\ This function from Charles R Greathouse IV, Aug 17 2011
A289622(n) = (1/2)*(2 + ((A046523(n)+A002322(n))^2) - A046523(n) - 3*A002322(n));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jul 16 2017
STATUS
approved