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A332460
a(n) = A005940(1+A065621(A156552(n))), with a(1) = 1.
3
1, 2, 3, 8, 5, 18, 7, 12, 27, 50, 11, 32, 13, 98, 75, 20, 17, 30, 19, 72, 147, 242, 23, 108, 125, 338, 45, 200, 29, 162, 31, 28, 363, 578, 245, 48, 37, 722, 507, 300, 41, 450, 43, 392, 243, 1058, 47, 500, 343, 70, 867, 968, 53, 42, 605, 588, 1083, 1682, 59, 128, 61, 1922, 675, 44, 845, 882, 67, 1352, 1587, 1250, 71, 180, 73, 2738, 105
OFFSET
1,2
FORMULA
a(1) = 1, and for n > 1, a(n) = A005940(1+A065621(A156552(n))).
a(p) = p for all primes p.
a(A003961(n)) = A003961(a(n)).
A008836(a(n)) = -1 for all n >= 2.
PROG
(PARI)
A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t }; \\ From A005940
A065621(n) = bitxor(n-1, n+n-1);
A156552(n) = {my(f = factor(n), p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res}; \\ From A156552
CROSSREFS
Cf. A332451 for a complementary sequence (after its initial 1).
Permutation of A026424 after the initial 1.
Sequence in context: A272878 A094181 A004730 * A168014 A050369 A070935
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 22 2020
STATUS
approved