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A372291
Numbers that occur exactly once in the odd bisection of A371094.
4
45, 69, 93, 141, 165, 189, 237, 261, 285, 333, 357, 381, 429, 453, 477, 525, 549, 573, 621, 645, 669, 717, 725, 741, 765, 813, 837, 861, 909, 933, 957, 1005, 1029, 1053, 1101, 1109, 1125, 1149, 1197, 1221, 1245, 1293, 1317, 1341, 1389, 1413, 1437, 1485, 1493, 1509, 1533, 1581, 1605, 1629, 1677, 1701, 1725, 1773, 1797
OFFSET
1,1
COMMENTS
Numbers that occur exactly once in array A371100.
LINKS
EXAMPLE
45 is present because A371094(k) = 45 for no other odd number than k=7.
PROG
(PARI)
A371094(n) = { my(m=1+3*n, e=valuation(m, 2)); ((m*(2^e)) + (((4^e)-1)/3)); };
isA372291(n) = if(!(n%2), 0, my(c=0); forstep(k=1, n, 2, if(A371094(k)==n, c++; if(c>1, return(0)))); (c));
CROSSREFS
Setwise difference A372290 \ A372292.
Sequence in context: A172466 A038494 A026043 * A330850 A053720 A259218
KEYWORD
nonn
AUTHOR
Antti Karttunen, Apr 26 2024
STATUS
approved