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.
Original entry on oeis.org
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
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.
-
Do[d=IntegerDigits[n];k=Length[d];If[PrimePi[n]==Sum[d[[j]]^j, {j, k}], Print[n]], {n, 0, 170000000}]
A112720
Numbers m such that phi(m) = 1^d_1 + 2^d_2 + ... + k^d_k where d_1 d_2 ... d_k is the decimal expansion of m.
Original entry on oeis.org
1, 2, 6883, 1132856, 11059812
Offset: 1
phi(11059812) = 1^1 + 2^1 + 3^0 + 4^5 + 5^9 + 6^8 + 7^1 + 8^2 so 11059812 is in the sequence.
-
Do[d=IntegerDigits[n];k=Length[d];If[EulerPhi[n]==Sum[j^d[[j]], {j, k}], Print[n]], {n, 70000000}]
A112721
Numbers m such that phi(m) = d_1^1 + d_2^2 + ... + d_k^k where d_1 d_2 ... d_k is the decimal expansion of m.
Original entry on oeis.org
1, 44, 84, 5676, 32186, 35097, 128476, 527048, 700298, 12141094, 43874279, 58730238, 303387848, 2277279428
Offset: 1
phi(12141094) = 1^1 + 2^2 + 1^3 + 4^4 + 1^5 + 0^6 + 9^7 + 4^8 = 4848768 so 12141094 is in the sequence.
-
Do[d=IntegerDigits[n];k=Length[d];If[EulerPhi[n]==Sum[d[[j]]^j, {j, k}], Print[n]], {n, 30000000}]
Showing 1-3 of 3 results.
Comments