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A082377 Numbers k such that rad(k) - phi(k) <= 1, where rad = A007947 and phi = A000010. 2
1, 2, 3, 4, 5, 7, 8, 9, 11, 13, 16, 17, 18, 19, 23, 24, 25, 27, 29, 31, 32, 36, 37, 40, 41, 43, 45, 47, 48, 49, 50, 53, 54, 56, 59, 61, 63, 64, 67, 71, 72, 73, 75, 79, 80, 81, 83, 88, 89, 96, 97, 98, 99, 100, 101, 103, 104, 107, 108, 109, 112, 113, 117, 120, 121, 125, 127 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..67.

PROG

(PARI) is(n)=my(f=factor(n)[, 1], r=prod(i=1, #f, f[i])); r-n/r*prod(i=1, #f, f[i]-1)<=1 \\ Charles R Greathouse IV, Feb 21 2013

CROSSREFS

Cf. A000010 (phi), A007947 (rad).

Sequence in context: A062491 A087092 A046684 * A166401 A329131 A334965

Adjacent sequences:  A082374 A082375 A082376 * A082378 A082379 A082380

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Apr 10 2003

STATUS

approved

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Last modified October 21 19:16 EDT 2021. Contains 348155 sequences. (Running on oeis4.)