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A167348 Let a(n) be the n-th term of the sequence. Let m = primorial(a(n)); m is the minimum positive integer such that m/phi(m) >= n. 0
2, 2, 3, 7, 13, 23, 43, 79, 149, 257, 461, 821, 1451, 2549, 4483, 7879, 13859, 24247, 42683, 75037, 131707, 230773, 405401, 710569, 1246379, 2185021, 3831913, 6720059, 11781551, 20657677, 36221753, 63503639, 111333529, 195199289 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A variant of A091440, which is the main entry for this sequence.

LINKS

Table of n, a(n) for n=1..34.

EXAMPLE

primorial(7) = 210; 210/phi(210) = 210/48 >= 4;

PROG

(PARI) al(lim) = local(mm, n, m); mm=3; n=2; m=1; forprime(x=3, lim, n*=x; m*= (x-1); if (n\m >= mm, print1(x", "); mm++)); /* This will generate all terms of this sequence from the 3rd onward, up to lim. The computation slows down for large values because of the size of the internal values. */

CROSSREFS

Cf. A091440.

Sequence in context: A100683 A153940 A049905 * A068524 A184841 A109277

Adjacent sequences:  A167345 A167346 A167347 * A167349 A167350 A167351

KEYWORD

nonn

AUTHOR

Fred Schneider, Aug 13 2009

EXTENSIONS

Edited and extended by Franklin T. Adams-Watters and N. J. A. Sloane, Aug 29 2009

STATUS

approved

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Last modified August 18 17:37 EDT 2017. Contains 290732 sequences.