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A322825
A variant of A322827.
2
1, 2, 6, 4, 36, 30, 18, 8, 216, 450, 210, 900, 108, 150, 54, 16, 1296, 6750, 7350, 13500, 44100, 2310, 22050, 27000, 648, 2250, 1470, 4500, 324, 750, 162, 32, 7776, 101250, 257250, 202500, 1543500, 177870, 771750, 405000, 9261000, 2668050, 30030, 5336100, 4630500, 889350, 2315250, 810000, 3888, 33750, 51450, 67500
OFFSET
0,2
FORMULA
A001221(a(n)) = A005811(n).
A001222(a(n)) = A227183(n).
A046523(a(n)) = A322827(n).
PROG
(PARI) A322825(n) = if(!n, 1, my(rl=1, m=1, p=2, eb = (n%2)); n>>=1; while(n, if((n%2)==eb, rl++, eb = 1-eb; m *= p^rl; p = nextprime(1+p)); n >>= 1); m *= p^rl; (m));
(PARI) A322825(n) = if(!n, 1, my(bits = Vecrev(binary(n)), rl=1, o = List([])); for(i=2, #bits, if(bits[i]==bits[i-1], rl++, listput(o, rl))); listput(o, rl); my(es=Vec(o), m=1); for(i=1, #es, m *= prime(i)^es[i]); (m));
CROSSREFS
Cf. A005811, A227183, A322827 (the main entry).
Sequence in context: A293011 A108435 A322827 * A347555 A215408 A264609
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 16 2019
STATUS
approved