A237522 - OEIS

A237522

Numbers k such that phi(k) + sigma(k) = reversal(k) - 1.

25, 165261124, 1698757933

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

a(4), if it exists, is larger than 10^13.

LINKS

Table of n, a(n) for n=1..3.

EXAMPLE

k = 165261124 is a term, because phi(k) = 67233600, sigma(k) = 353928960 and 67233600 + 353928960 = 421162561 - 1, where 421162561 is the reversal of 165261124.

CROSSREFS

Cf. A000010, A000203, A004086.

Cf. A070272, A230004, A230005, A230006, A230019, A136544, A237521.

Sequence in context: A228536 A191559 A279039 * A347810 A116197 A023924

Adjacent sequences: A237519 A237520 A237521 * A237523 A237524 A237525

KEYWORD

base,nonn,bref,more

AUTHOR

Giovanni Resta, Feb 08 2014

STATUS

approved