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A167758 Numbers n such that d(n)=nonisolated nonprime. 0
1, 24, 30, 36, 40, 42, 48, 54, 56, 66, 70, 78, 80, 88, 100, 102, 104, 105, 110, 112, 114, 120, 128, 130, 135, 136, 138, 144, 152, 154, 162, 165, 168, 170, 174, 176, 182, 184, 186, 189, 190, 192, 195, 196, 208, 210, 216, 222, 225, 230, 231, 232, 238, 240, 246 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Where 0, 1, 8, 9, 10, 14, 15, 16, 20,.. are nonisolated nonprimes A164276. Numbers n such that number of divisors of n is nonisolated nonprime. Or, the positions of nonisolated nonprimes in A000005.

LINKS

Table of n, a(n) for n=1..55.

FORMULA

A000005(a(n))=nonisolated nonprime.

EXAMPLE

A000005(1=a(1))=1; A000005(24=a(2))=8; A000005(30=a(3))=8; A000005(36=a(4))=9.

CROSSREFS

Cf. A000005, A164276.

Sequence in context: A114635 A077969 A122181 * A248693 A075422 A230195

Adjacent sequences:  A167755 A167756 A167757 * A167759 A167760 A167761

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Nov 10 2009

EXTENSIONS

Corrected (152 inserted) by R. J. Mathar, May 30 2010

STATUS

approved

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Last modified January 25 03:49 EST 2020. Contains 331241 sequences. (Running on oeis4.)