A379125 Sum of divisors of those odd squares k for which A379113(k) > 1, i.e., k that have a proper unitary divisor d > 1 such that A048720(A065621(sigma(d)),sigma(k/d)) is equal to sigma(k).

403, 4123, 4953, 18291, 46101, 73749, 133939, 400179, 291441, 542469, 618673, 1153633, 1119859, 1098867, 1077699, 1599249, 2309619, 6848721, 20421219, 20131059, 17598529, 17022999, 44205381, 59669253, 80520921, 68946969, 88131729, 83998281, 88119813, 97595019, 102760497, 137273157, 147291249, 211492119, 574669953

Offset

1,1

Links

Antti Karttunen, Table of n, a(n) for n = 1..2025

Index entries for sequences defined by congruent products between domains N and GF(2)[X].

Index entries for sequences related to polynomials in ring GF(2)[X].

Index entries for sequences related to sigma(n).

Formula

a(n) = A000203(A379121(n)).

a(n) = A277320(sigma(A379123(n)), sigma(A379124(n))).

a(n) = sigma(A379123(n)) * sigma(A379124(n)).

Prog

(PARI) forstep(n=1, oo, 2, if(A379113(n^2)>1, k++; print1(sigma(n^2), ", ")));

Crossrefs

Cf. A000203, A048720, A065621, A277320, A379113, A379121, A379123, A379124.

Sequence in context: A083815 A250893 A261857 * A165808 A283662 A097741

Adjacent sequences: A379122 A379123 A379124 * A379126 A379127 A379128

Keyword

nonn

Author

Antti Karttunen, Dec 18 2024

Status

approved