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A306829
a(1) = 1; a(n+1) is the smallest k > a(n) such that 2^k == 2^a(n) (mod a(n)).
1
1, 2, 3, 5, 9, 15, 19, 37, 73, 82, 102, 110, 130, 142, 177, 235, 327, 363, 473, 543, 723, 747, 993, 1023, 1033, 1291, 2581, 2889, 3843, 3903, 5203, 5973, 6153, 7029, 7239, 7365, 8345, 10013, 10373, 10593, 12183, 12313, 13192, 13240, 13300, 13480, 13564, 13677
OFFSET
1,2
COMMENTS
The number of consecutive terms with the same parity: 1, 1, 7, 5, 28, 5, 16, 13, 47, 4, 70, 6, 56, 4, 32, 11, 17, 21, 22, 11, 2, 20, 67, 13, 22, 36, 8, 9,101, 47, 24, 4, 1, 7, 2, 79, 20, 71, 47, 92, 36, 57, 90, 38, 167, 215, 31, 17, 62, ... i.e.; 1 odd term, 1 even term, 7 odd terms, 5 even terms, 28 odd terms, 5 even terms, ...
LINKS
FORMULA
a(n+1) = a(n) + ord_{A000265(a(n))}(2), where A000265(m) is the odd part of m.
MAPLE
A[1]:= 1:
for n from 2 to 100 do A[n]:= A[n-1] + numtheory:-order(2, A[n-1]/2^padic:-ordp(A[n-1], 2)) od:
seq(A[n], n=1..100); # Robert Israel, Apr 10 2019
PROG
(PARI) odd(n) = n >> valuation(n, 2);
lista(nn) = {a = 1; print1(a, ", "); for (n=2, nn, a = a + znorder(Mod(2, odd(a))); print1(a, ", "); ); } \\ Michel Marcus, Mar 23 2019
CROSSREFS
Sequence in context: A101461 A085897 A361906 * A067798 A205536 A281704
KEYWORD
nonn
AUTHOR
Thomas Ordowski, Mar 12 2019
EXTENSIONS
More terms from Amiram Eldar, Mar 12 2019
STATUS
approved