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 A243056 If n is the i-th prime, p_i = A000040(i), then a(n) = i, otherwise the difference between the indices of the smallest and the largest prime dividing n: for n = p_i * ... * p_k, where p_i <= ... <= p_k, a(n) = (k-i); a(1) = 0 by convention. 6
 0, 1, 2, 0, 3, 1, 4, 0, 0, 2, 5, 1, 6, 3, 1, 0, 7, 1, 8, 2, 2, 4, 9, 1, 0, 5, 0, 3, 10, 2, 11, 0, 3, 6, 1, 1, 12, 7, 4, 2, 13, 3, 14, 4, 1, 8, 15, 1, 0, 2, 5, 5, 16, 1, 2, 3, 6, 9, 17, 2, 18, 10, 2, 0, 3, 4, 19, 6, 7, 3, 20, 1, 21, 11, 1, 7, 1, 5, 22, 2, 0, 12, 23, 3, 4, 13, 8, 4, 24, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Antti Karttunen, Table of n, a(n) for n = 1..10000 FORMULA a(1) = 0, for n>1, if n = A000040(i), a(n) = i, otherwise a(n) = A061395(n) - A055396(n) = A243055(n). PROG (Scheme) (define (A243056 n) (if (prime? n) (A049084 n) (A243055 n))) CROSSREFS Useful when computing A243057 or A243059. A025475 (prime powers that are not primes) gives the positions of zeros. Differs from A241917 for the first time at n=18. Cf. A243055, A241919, A242411, A049084, A027748, A055396, A061395. Sequence in context: A292801 A277697 A241917 * A279119 A249738 A110514 Adjacent sequences:  A243053 A243054 A243055 * A243057 A243058 A243059 KEYWORD nonn AUTHOR Antti Karttunen, May 31 2014 STATUS approved

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Last modified September 18 11:42 EDT 2018. Contains 315130 sequences. (Running on oeis4.)