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A285318
a(n) = A048675(A285317(n)).
2
18, 36, 19, 8194, 37, 2147483648, 18014398509481984, 8195, 2056, 18014398509481985, 67108868, 16400, 2057, 158456325028528675187087900672, 2097184, 67108869, 5986310706507378352962293074805895248510699696029696, 11972621413014756705924586149611790497021399392059392, 16401, 295147905179352825858, 158456325028528675187087900673, 34359738376
OFFSET
1,1
LINKS
FORMULA
a(n) = A048675(A285317(n)).
PROG
(PARI)
A019565(n) = {my(j, v); factorback(Mat(vector(if(n, #n=vecextract(binary(n), "-1..1")), j, [prime(j), n[j]])~))}; \\ This function from M. F. Hasler
isA285317(n) = (issquarefree(n) & (A019565(n) < n));
A048675(n) = my(f = factor(n)); sum(k=1, #f~, f[k, 2]*2^primepi(f[k, 1]))/2; \\ Michel Marcus, Oct 10 2016
n=0; k=1; while(k <= 130, n=n+1; if(isA285317(n), write("b285318.txt", k, " ", A048675(n)); k=k+1));
(Scheme) (define (A285318 n) (A048675 (A285317 n)))
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Apr 18 2017
STATUS
approved