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A215240 Sum of the numbers p such that phi(p) = n, where phi is Euler's totient function. 4
3, 13, 0, 35, 0, 48, 0, 105, 0, 33, 0, 166, 0, 0, 0, 231, 0, 138, 0, 218, 0, 69, 0, 621, 0, 0, 0, 87, 0, 93, 0, 581, 0, 0, 0, 655, 0, 0, 0, 833, 0, 276, 0, 299, 0, 141, 0, 1514, 0, 0, 0, 159, 0, 243, 0, 377, 0, 177, 0, 1114, 0, 0, 0, 1315, 0, 201, 0, 0, 0, 213, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

These terms (greater than 0) are not unique. The first duplicate appears at a(256) = a(2236) = 6711.

LINKS

T. D. Noe, Table of n, a(n) for n = 1..10000

D. Bressoud, CNT.m Computational Number Theory Mathematica package.

MATHEMATICA

Needs["CNT`"]; Table[Total[PhiInverse[n]], {n, 100}]

CROSSREFS

Cf. A002181 (smallest inverse), A006511 (largest inverse), A217842 (product of inverses).

Cf. A032447 (inverse of phi).

Sequence in context: A226129 A167368 A318165 * A068697 A010258 A107774

Adjacent sequences:  A215237 A215238 A215239 * A215241 A215242 A215243

KEYWORD

nonn

AUTHOR

T. D. Noe, Oct 12 2012

STATUS

approved

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Last modified September 24 18:11 EDT 2022. Contains 356949 sequences. (Running on oeis4.)