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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).
1
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
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), ", ")));
KEYWORD
nonn,new
AUTHOR
Antti Karttunen, Dec 18 2024
STATUS
approved