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 A328461 a(n) = A276156(n) / A002110(A007814(n)). 12
 1, 1, 3, 1, 7, 4, 9, 1, 31, 16, 33, 6, 37, 19, 39, 1, 211, 106, 213, 36, 217, 109, 219, 8, 241, 121, 243, 41, 247, 124, 249, 1, 2311, 1156, 2313, 386, 2317, 1159, 2319, 78, 2341, 1171, 2343, 391, 2347, 1174, 2349, 12, 2521, 1261, 2523, 421, 2527, 1264, 2529, 85, 2551, 1276, 2553, 426, 2557, 1279, 2559, 1, 30031, 15016, 30033, 5006 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS A276156(n) converts the binary expansion of n to a number whose primorial base representation has the same digits of 0's and 1's, thus each one of its terms is a unique sum of distinct primorial numbers. In this sequence that sum is then divided by the largest primorial that divides it, which only depends on the position of the least significant 1-bit in the binary expansion of the original n, that is, the 2-adic valuation of n. LINKS Antti Karttunen, Table of n, a(n) for n = 1..8192 FORMULA a(n) = A276156(n) / A002110(A007814(n)). a(n) = A111701(A276156(n)). PROG (PARI) A002110(n) = prod(i=1, n, prime(i)); A276156(n) = { my(p=2, pr=1, s=0); while(n, if(n%2, s += pr); n >>= 1; pr *= p; p = nextprime(1+p)); (s); }; A328461(n) = (A276156(n)/A002110(valuation(n, 2))); CROSSREFS Cf. A000265, A002110, A007814, A111701, A276154, A276156. Cf. A328462 (bisection, also row 1 of array A328464 which shows the same information in tabular form). Cf. A328471, A328472, A328473, A328474. Sequence in context: A283764 A010603 A269423 * A341494 A210198 A271258 Adjacent sequences:  A328458 A328459 A328460 * A328462 A328463 A328464 KEYWORD nonn AUTHOR Antti Karttunen, Oct 16 2019 STATUS approved

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Last modified June 13 05:41 EDT 2021. Contains 344981 sequences. (Running on oeis4.)