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A112719
Numbers m such that pi(m) = d_1^1 + d_2^2 + ... + d_k^k where d_1 d_2 ... d_k is the decimal expansion of m.
3
0, 12, 160, 253, 382, 3664, 4683, 9285, 66290, 207735, 390481, 3748380, 7884391, 9136095, 11187665, 12690170, 15008945, 32067066, 34152082, 43470982, 311506482, 315458182, 317195680, 317583584, 789530607, 803190747, 818360167
OFFSET
1,2
COMMENTS
This sequence is finite and the largest term is less than 10^73.
EXAMPLE
43470982 is in the sequence because pi(43470982) = 4^1 + 3^2 + 4^3 + 7^4 + 0^5 + 9^6 + 8^7 + 2^8 = 2631327.
MATHEMATICA
Do[d=IntegerDigits[n]; k=Length[d]; If[PrimePi[n]==Sum[d[[j]]^j, {j, k}], Print[n]], {n, 0, 170000000}]
CROSSREFS
KEYWORD
base,fini,nonn
AUTHOR
Farideh Firoozbakht, Sep 17 2005
EXTENSIONS
a(21)-a(27) from Donovan Johnson, Nov 09 2010
STATUS
approved