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A277317
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Numbers n such that A277333(n) is a prime.
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6
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3, 6, 18, 30, 270, 450, 630, 2310, 6750, 9450, 22050, 510510, 727650, 2668050, 3543750, 4961250, 25467750, 29099070
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OFFSET
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1,1
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COMMENTS
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Sequence A277316 sorted into ascending order. See comments in that entry.
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LINKS
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PROG
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(PARI)
\\ Naive program that does not work very far:
A003961(n) = my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); \\ From Michel Marcus
A048675(n) = my(f = factor(n)); sum(k=1, #f~, f[k, 2]*2^primepi(f[k, 1]))/2; \\ Michel Marcus, Oct 10 2016
isA277317 = n -> isprime(A277333(n)); \\ Naive version, very slow.
isA277317(n) = { my(k); if(3==n, 1, if(n%2 || (omega(n) < A061395(n)), 0, k = A048675(n); if((A260443(k) == n), isprime(k), 0))); }; \\ Somewhat optimized.
i=0; n=0; while(i < 30, n++; if(isA277317(n), i++; write("b277317.txt", i, " ", n)));
;; Doing search in another order:
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CROSSREFS
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Also, after the initial term, the intersection of A277200 and A277319.
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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