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A341509
a(n) = 2^j if n is of the form 2^i - 2^j with i > j, and 0 otherwise.
3
0, 1, 2, 1, 4, 0, 2, 1, 8, 0, 0, 0, 4, 0, 2, 1, 16, 0, 0, 0, 0, 0, 0, 0, 8, 0, 0, 0, 4, 0, 2, 1, 32, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 0, 0, 0, 0, 0, 0, 0, 8, 0, 0, 0, 4, 0, 2, 1, 64, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 32, 0, 0, 0, 0, 0, 0, 0, 0
OFFSET
0,3
FORMULA
a(0) = 0, and for n >= 1, a(n) = A340375(n) * A006519(n).
a(n) = A156552(A014963(A005940(1+n))).
PROG
(PARI)
A006519(n) = (1<<valuation(n, 2));
A340375(n) = if(n<5, 1, n>>=valuation(n, 2); n++; n>>valuation(n, 2)==1); \\ After function "is" given in A023758
A341509(n) = if(!n, n, A340375(n)*A006519(n));
CROSSREFS
Cf. A023758 (after its initial zero, gives the positions nonzero terms).
Sequence in context: A137629 A220504 A087569 * A048614 A001442 A226952
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 13 2021
STATUS
approved