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A105604
Sylvester dividends for Jacobsthal numbers.
1
1, 1, 1, 1, 1, 3, 1, 5, 3, 11, 1, 105, 1, 43, 33, 85, 1, 1197, 1, 1705, 129, 683, 1, 23205, 11, 2731, 171, 27305, 1, 2370291, 1, 21845, 2049, 43691, 473, 5679765, 1, 174763, 8193, 5941925, 1, 621456339, 1, 6990505, 622611, 2796203, 1, 1437248085, 43, 346729141, 131073, 111848105, 1, 22861753173, 7513, 1521134245
OFFSET
1,6
COMMENTS
Divide each Jacobsthal number by its primitive part.
LINKS
FORMULA
a(n) = A001045(n)/A105603(n).
PROG
(PARI)
A001045(n) = ((2^n - ((-1)^n)) / 3);
A105603(n) = if(1==n, n, (-1)^eulerphi(n)*polcyclo(n, -2)); \\ After Wolfdieter Lang's formula in that entry.
A105604(n) = (A001045(n)/A105603(n)); \\ Antti Karttunen, Nov 01 2017
CROSSREFS
Sequence in context: A195835 A077881 A129095 * A117576 A112447 A289360
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Apr 15 2005
EXTENSIONS
More terms from Antti Karttunen, Nov 01 2017
STATUS
approved