A049454 a(n) = 1 + Sum_{i=1..n} phi(i)^2.

1, 2, 3, 7, 11, 27, 31, 67, 83, 119, 135, 235, 251, 395, 431, 495, 559, 815, 851, 1175, 1239, 1383, 1483, 1967, 2031, 2431, 2575, 2899, 3043, 3827, 3891, 4791, 5047, 5447, 5703, 6279, 6423, 7719, 8043, 8619, 8875, 10475, 10619, 12383

Offset

0,2

Links

Harvey P. Dale, Table of n, a(n) for n = 0..1000

Mathematica

Table[1+Sum[EulerPhi[i]^2, {i, n}], {n, 0, 50}] (* Harvey P. Dale, Mar 21 2020 *)

Prog

(PARI) a(n) = 1 + sum(i=1, n, eulerphi(i)^2); \\ Michel Marcus, Mar 07 2020

Crossrefs

Cf. A000010 (phi), A005728.

Sequence in context: A354540 A112843 A036651 * A095055 A305750 A107857

Adjacent sequences: A049451 A049452 A049453 * A049455 A049456 A049457

Keyword

nonn

Author

N. J. A. Sloane

Status

approved