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A342457
Terms of A342456 prime-shifted so far towards lower primes that they become even: a(n) = 2*A246277(A342456(n)).
4
2, 2, 2, 4, 2, 4, 6, 6, 2, 4, 64, 16, 324, 36, 10, 36, 2, 4, 64, 16, 2304, 96, 486, 24, 7290, 104976, 21600, 1296, 1708593750000, 100, 93750, 10, 2, 4, 64, 16, 144, 6, 216, 6, 172186884, 7776, 2160, 216, 216000000, 236196, 10497600, 54, 10935000000000, 53144100, 1476225000000, 7290, 122500000000, 10935000, 140, 360
OFFSET
0,1
COMMENTS
These terms have the same prime signature as the corresponding terms in A342456, thus applying omega and bigomega to these gives the same derived sequences A342461 and A342462.
FORMULA
a(n) = 2*A246277(A342456(n)) = 2*A329038(A329886(n)).
PROG
(PARI)
A246277(n) = if(1==n, 0, my(f = factor(n), k = primepi(f[1, 1])-1); for (i=1, #f~, f[i, 1] = prime(primepi(f[i, 1])-k)); factorback(f)/2);
A342457(n) = 2*A246277(A342456(n)); \\ Uses also code from A342456.
CROSSREFS
Sequence in context: A366771 A217982 A184727 * A286849 A098069 A173738
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 15 2021
STATUS
approved