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 A113498 Ascending descending base exponent transform of omega(n) (A001221). 5
 1, 2, 3, 4, 6, 7, 8, 9, 13, 12, 14, 15, 21, 19, 24, 21, 29, 28, 30, 28, 40, 35, 41, 42, 46, 41, 53, 44, 59, 52, 61, 55, 79, 55, 69, 66, 86, 70, 90, 73, 94, 93, 91, 81, 121, 88, 114, 103, 123, 95, 137, 102, 138, 122, 132, 114, 168, 121, 144, 145, 159, 137, 180 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,2 LINKS G. C. Greubel, Table of n, a(n) for n = 2..5000 FORMULA a(n) = Sum_{i=1..n} (omega(k))^(omega(n-k+2)). a(n) = Sum_{i=1..n} A001221(k))^(A001221(n-k+2)). EXAMPLE Since omega(n) = A001221(n) = 0, 1, 1, 1, 1, 2, 1, 1, 1, 2 and we skip the initial zero term, we have: a(1) = 1^1 = 1. a(2) = 1^1 + 1^1 = 2. a(3) = 1^1 + 1^1 + 1^1 = 3. a(4) = 1^1 + 1^1 + 1^1 + 1^1 = 4. a(5) = 1^1 + 1^1 + 1^1 + 1^1 + 2^1 = 6. a(9) = 1^1 + 1^1 + 1^1 + 1^1 + 2^2 + 1^1 + 1^1 + 1^1 + 2^1 = 13. MATHEMATICA Table[Sum[PrimeNu[k]^(PrimeNu[n - k + 2]), {k, 2, n}], {n, 2, 50}] (* G. C. Greubel, May 18 2017 *) PROG (PARI) for(n=2, 25, print1(sum(k=2, n, omega(k)^(omega(n-k+2))), ", ")) \\ G. C. Greubel, May 18 2017 CROSSREFS Cf. A001221, A113320, A005408, A113122, A113153, A113154, A113336, A113271, A113258, A113257, A113231, A087316, A113208. Sequence in context: A233576 A128170 A018490 * A036796 A209643 A039123 Adjacent sequences:  A113495 A113496 A113497 * A113499 A113500 A113501 KEYWORD easy,nonn AUTHOR Jonathan Vos Post, Jan 10 2006 EXTENSIONS Corrected and extended by Giovanni Resta, Jun 13 2016 Formulas corrected by G. C. Greubel, May 18 2017 STATUS approved

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Last modified October 20 15:29 EDT 2019. Contains 328267 sequences. (Running on oeis4.)