A338190 - OEIS

A338190

Integers m such that A337454(m) = tau(m), the number of divisors of n.

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 14, 15, 16, 17, 18, 19, 22, 23, 25, 26, 27, 29, 30, 31, 32, 34, 36, 37, 38, 39, 41, 43, 45, 46, 47, 49, 50, 51, 53, 54, 58, 59, 61, 62, 64, 67, 71, 73, 74, 75, 78, 79, 81, 82, 83, 85, 86, 87, 89, 90, 91, 94, 97, 98, 99, 101, 102

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OFFSET

1,2

LINKS

Table of n, a(n) for n=1..69.

PROG

(PARI) f(n) = sumdiv(n, d, n % (sum(m=0, n-1, Mod(m, n)^d == m)/sum(m=0, n-1, -Mod(m, n)^d == m)) == 0); \\ A337454

isok(n) = f(n) == numdiv(n);

CROSSREFS

Cf. A000005, A337454, A338189.

Sequence in context: A289812 A362622 A206551 * A247762 A343268 A107909

Adjacent sequences: A338187 A338188 A338189 * A338191 A338192 A338193

KEYWORD

nonn

AUTHOR

Michel Marcus, Oct 15 2020

STATUS

approved