A065388 Record values for sigma(m) + phi(m): sum of sigma and totient is larger than for any previous number.

2, 4, 6, 9, 10, 14, 19, 22, 32, 39, 45, 50, 68, 80, 103, 106, 108, 140, 144, 184, 219, 248, 258, 284, 316, 392, 451, 528, 594, 624, 672, 808, 816, 915, 948, 955, 1088, 1266, 1440, 1640, 1704, 1824, 1843, 2020, 2031, 2176, 2208, 2610, 3072, 3304, 3512, 3888

Offset

1,1

Links

Harry J. Smith, Table of n, a(n) for n=1..500

Formula

a(n) = sigma(A015702(n)) + phi(A015702(n));

a(n) = A000203(A015702(n)) + A000010(A015702(n).

Prog

(PARI) { n=r=0; for (m=1, 10^9, x=sigma(m) + eulerphi(m); if (x > r, r=x; write("b065388.txt", n++, " ", x); if (n==500, return)) ) } \\ Harry J. Smith, Oct 17 2009

Crossrefs

Cf. A000010, A000203, A065387, A015702.

Sequence in context: A065387 A219787 A331006 * A157936 A338348 A184978

Adjacent sequences: A065385 A065386 A065387 * A065389 A065390 A065391

Keyword

nonn

Author

Labos Elemer, Nov 05 2001

Status

approved