1,1

Table of n, a(n) for n=1..73.

a(n) = A007953(A001101(n)).

For n = 42:

- A001101(42) = 555,

- A007953(555) = 15,

- hence a(42) = 15.

(PARI) for (n=1, 1168, if (n%(s=sumdigits(n))==0 && isprime(n/s), print1 (s", ")))

Cf. A001101, A007953, A334375.

Sequence in context: A276558 A196829 A019879 * A003565 A238105 A166203

Adjacent sequences: A334373 A334374 A334375 * A334377 A334378 A334379

nonn,base

Rémy Sigrist, Apr 25 2020

approved