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A082129 Rounded base-2 logarithm of A082128(n+4). 1
3, 1, 5, 4, 6, 9, 17, 22, 33, 53, 76, 114, 171, 260, 390, 585, 874, 1311, 1970 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..18.

PROG

(PARI) p=21*4*5*13; for(n=1, 50, v=divisors(p); r=sqrt(p); t=0; for(k=1, matsize(v)[2], if(v[k]>=r, t=k; break)); if(v[t]^2==p, u=t, u=t-1); if(v[t]-v[u]<2, u=u-1; t=t+1); print1(round(log(v[t]-v[u])/log(2))", "); p=p*(v[t]-v[u]))

CROSSREFS

Cf. A082127.

Sequence in context: A154947 A152747 A010847 * A159970 A096374 A007085

Adjacent sequences:  A082126 A082127 A082128 * A082130 A082131 A082132

KEYWORD

nonn,hard

AUTHOR

Ralf Stephan, Apr 04 2003

STATUS

approved

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Last modified May 25 23:54 EDT 2019. Contains 323576 sequences. (Running on oeis4.)