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A331749
a(n) = A002487(A163511(n)) - A002487(n).
3
1, 0, 0, 0, 0, 1, 0, 0, 0, 4, 1, 2, 0, -1, 0, -1, 0, 9, 4, 4, 1, 10, 2, 2, 0, 5, -1, 1, 0, 1, -1, 0, 0, 16, 9, 34, 4, 23, 4, 37, 1, 5, 10, 10, 2, 14, 2, 4, 0, 7, 5, 11, -1, 5, 1, 6, 0, -4, 1, 0, -1, -3, 0, -1, 0, 57, 16, 116, 9, 98, 34, 84, 4, 69, 23, 103, 4, 9, 37, 98, 1, 52, 5, 70, 10, 19, 10, 39, 2, 19, 14, 38, 2, 34, 4, 18, 0, 39
OFFSET
0,10
FORMULA
a(n) = A323901(n) - A002487(n) = A002487(A163511(n)) - A002487(n).
a(2^n) = 0 for all n >= 0.
PROG
(PARI)
A002487(n) = { my(a=1, b=0); while(n>0, if(bitand(n, 1), b+=a, a+=b); n>>=1); (b); }; \\ From A002487
A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t }; \\ From A005940
A054429(n) = ((3<<#binary(n\2))-n-1); \\ From A054429
A163511(n) = if(!n, 1, A005940(1+A054429(n)));
A331749(n) = (A002487(A163511(n)) - A002487(n));
CROSSREFS
KEYWORD
sign
AUTHOR
Antti Karttunen, Feb 05 2020
STATUS
approved