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 A120430 Greater of prime powers that differ by 1. In other words, numbers n such that n-1 and n are prime powers. 0
 2, 3, 4, 5, 8, 9, 17, 32, 128, 257, 8192, 65537, 131072, 524288, 2147483648, 2305843009213693952, 618970019642690137449562112, 162259276829213363391578010288128 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS See comments in A006549. LINKS FORMULA a(n) = A006549(n) + 1. - Michel Marcus, Aug 25 2013 PROG (PARI) isokp(n) = (n==1) || isprime(n) || (ispower(n, , &k) && isprime(k)); isok(n) = isokp(n) && isokp(n-1); \\ Michel Marcus, Aug 25 2013 CROSSREFS Cf. A006549. Sequence in context: A330400 A306044 A263581 * A295033 A152606 A057911 Adjacent sequences:  A120427 A120428 A120429 * A120431 A120432 A120433 KEYWORD nonn AUTHOR Greg Huber, Jul 13 2006 STATUS approved

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Last modified July 27 21:21 EDT 2021. Contains 346316 sequences. (Running on oeis4.)