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A073900 a(1) = 1; then k-th prime prime(k) followed by Floor[e^k] consecutive composite numbers not occurring earlier. 1
1, 2, 4, 6, 3, 8, 9, 10, 12, 14, 15, 16, 5, 18, 20, 21, 22, 24, 25, 26, 27, 28, 30, 32, 33, 34, 35, 36, 38, 39, 40, 42, 44, 7, 45, 46, 48, 49, 50, 51, 52, 54, 55, 56, 57, 58, 60, 62, 63, 64, 65, 66, 68, 69, 70, 72, 74, 75, 76, 77, 78, 80, 81, 82, 84, 85, 86, 87, 88, 90, 91, 92 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Primes grow faster than composites. Question: For what (the smallest) value of m a(m) is prime and more than the previous term which is obviously composite.?

LINKS

Table of n, a(n) for n=1..72.

EXAMPLE

a(2) =2 and Floor[e] = 2 hence a(3) and a(4) are 4 and 6 respectively. a(5) = 3 (the second prime) and Floor[e^2]=7, hence next 7 terms are 8,9,10,12,14,15 and 16.

CROSSREFS

Cf. A073899.

Sequence in context: A073899 A232846 A101543 * A026200 A026218 A181473

Adjacent sequences:  A073897 A073898 A073899 * A073901 A073902 A073903

KEYWORD

nonn

AUTHOR

Amarnath Murthy, Aug 18 2002

EXTENSIONS

Edited by T. D. Noe, Apr 13 2009

STATUS

approved

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Last modified December 7 22:50 EST 2021. Contains 349590 sequences. (Running on oeis4.)