A112718 Numbers n such that pi(n)=1^d_1+2^d_2+...+k^d_k where d_1 d_2 ... d_k is the decimal expansion of n.

2, 12, 23, 113, 151, 5924, 14254, 106545, 1915765, 2798136, 31749441, 35282317, 35389065, 35389165, 105227821, 141291863, 193789064, 326730783, 839512048, 882012907, 884676937, 2780026914, 2997751947, 8493184690, 8493955191

Offset

1,1

Comments

The largest term is less than 10^12 because if m>12 then 1^9+2^9+...+n^9 < pi(10^(m-1)). There is no further term up to 41*10^7.

Links

Giovanni Resta, Table of n, a(n) for n = 1..33 (full sequence)

Example

326730783 is in the sequence because pi(326730783)=1^3+2^2+3^6+
4^7+5^3+6^0+7^7+8^8+9^3.

Mathematica

Do[d=IntegerDigits[n]; k=Length[d]; If[PrimePi[n]==Sum[j^d[[j]], {j, k}], Print[n]], {n, 410000000}]

Crossrefs

Cf. A035138, A112719, A112720.

Sequence in context: A012545 A009514 A192851 * A365500 A117301 A141079

Adjacent sequences: A112715 A112716 A112717 * A112719 A112720 A112721

Keyword

base,fini,full,nonn

Author

Farideh Firoozbakht, Sep 17 2005

Extensions

a(19)-a(25) from Donovan Johnson, Nov 09 2010

Status

approved