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A291373 a(n) is the smallest number k such that A001065(k) = A002110(n), or 0 if no such k exists. 0
2, 0, 6, 841, 0, 1722, 30018, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

a(10) = 4057230930. - Giovanni Resta, Aug 23 2017

LINKS

Table of n, a(n) for n=0..7.

FORMULA

a(n) = A070015(A002110(n)). - Michel Marcus, Aug 25 2017

EXAMPLE

a(5) = 1722 because sigma(1722) - 1722 = 2*3*5*7*11 = A002110(5) and 1722 is the least number with this property.

CROSSREFS

Cf. A001065, A002110, A070015, A153076, A291356.

Sequence in context: A305620 A294470 A283654 * A021487 A197391 A285174

Adjacent sequences:  A291370 A291371 A291372 * A291374 A291375 A291376

KEYWORD

nonn,hard,more

AUTHOR

Altug Alkan, Aug 23 2017

EXTENSIONS

a(7) confirmed by Giovanni Resta, Aug 23 2017

STATUS

approved

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Last modified August 10 14:50 EDT 2020. Contains 336381 sequences. (Running on oeis4.)