Numbers n such that n = concat(a,b) and n = phi(n) + phi(a) + phi(b), with a>0 and b>0, where phi(n) is the Euler totient function of n.

A258319

Numbers n such that n = concat(a,b) and n = phi(n) + phi(a) + phi(b), with a>0 and b>0, where phi(n) is the Euler totient function of n.

Terms

    a(0) =25a(1) =177a(2) =1177a(3) =2501a(4) =17105a(5) =21337a(6) =22681a(7) =32581a(8) =217009a(9) =409501a(10) =561601a(11) =577501a(12) =861841a(13) =1025821a(14) =1401841a(15) =1738081a(16) =2836465a(17) =8331361a(18) =10284193a(19) =19971901a(20) =20103001a(21) =27835921a(22) =31949921a(23) =34897501a(24) =100763053a(25) =107314217a(26) =111512701a(27) =121806001a(28) =150658561a(29) =155874001

External references