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A063710 Numbers k such that e(k) = s(k), where e(k) = eulerphi(sigma(k)+k) and s(n) = sigma(k-eulerphi(k)). 1
10, 22, 38, 58, 82, 182, 228, 244, 308, 346, 404, 446, 514, 524, 644, 922, 1020, 1214, 1484, 1522, 1538, 1582, 2104, 2408, 5600, 5924, 7596, 8420, 13352, 13378, 13738, 14686, 15012, 20128, 21272, 27084, 27580, 29312, 37158, 43946, 47284, 47468 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harry J. Smith, Table of n, a(n) for n = 1..350

PROG

(PARI) s(n) = sigma(n-eulerphi(n)); e(n) = eulerphi(sigma(n)+n); j = []; for(n = 1, 10^5, if(e(n) == s(n), j = concat(j, n))); j

(PARI) { n=0; for (x=2, 10^9, if (eulerphi(sigma(x) + x) == sigma(x - eulerphi(x)), write("b063710.txt", n++, " ", x); if (n==350, break)) ) } \\ Harry J. Smith, Aug 28 2009

CROSSREFS

Sequence in context: A177791 A028569 A014367 * A157917 A242234 A104867

Adjacent sequences:  A063707 A063708 A063709 * A063711 A063712 A063713

KEYWORD

easy,nonn

AUTHOR

Jason Earls, Aug 23 2001

STATUS

approved

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Last modified October 19 12:29 EDT 2019. Contains 328222 sequences. (Running on oeis4.)