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A066089 Smallest m such that A066088(m) = A001221(A001157(m)) = n. 0
2, 3, 10, 12, 52, 188, 1175, 4840, 25168, 90992, 896368, 8164112, 30997008, 233151408, 2111839632 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..15.

EXAMPLE

n = 5: a(5) = 52, sigma_2(52) = 2704+676+169+16+4+1 = 3570 = 2*3*5*7*17.

PROG

(PARI) { for (n=1, 100, m=1; while(omega(sigma(m, 2)) != n, m++); write("b066089.txt", n, " ", m) ) } \\ Harry J. Smith, Nov 12 2009

CROSSREFS

Cf. A001157, A001221, A066088.

Sequence in context: A069124 A218028 A067769 * A203235 A256214 A256213

Adjacent sequences:  A066086 A066087 A066088 * A066090 A066091 A066092

KEYWORD

nonn

AUTHOR

Labos Elemer, Dec 04 2001

EXTENSIONS

Terms a(11) - a(13) from Harry J. Smith, Nov 12 2009

a(14)-a(15) from Donovan Johnson, Apr 16 2013

STATUS

approved

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Last modified September 29 03:42 EDT 2020. Contains 337420 sequences. (Running on oeis4.)