A071855 Numbers n such that A067434(n) = A000720(n) + A000005(n).

1, 37, 41, 43, 47, 49, 58, 65, 69, 81, 85, 92, 128, 130, 135, 136, 154, 184, 208, 220, 228, 450, 540, 840

Offset

1,2

Comments

No further terms below 143260.

No further terms below 2*10^4. - Robert G. Wilson v

Links

Table of n, a(n) for n=1..24.

Mathematica

Select[ Range[10^3], Length[ FactorInteger[ Binomial[2#, # ]]] == PrimePi[ # ] + DivisorSigma[0, # ] & ]

Prog

(PARI) for(n=1, 1000, if(omega(binomial(2*n, n))=sum(i=1, n, isprime(i))+numdiv(n), print1(n, ", ")))

Crossrefs

Sequence in context: A111198 A081645 A069963 * A137675 A161725 A100722

Adjacent sequences: A071852 A071853 A071854 * A071856 A071857 A071858

Keyword

nonn

Author

Benoit Cloitre, Jun 09 2002

Status

approved