A327865 Numbers whose arithmetic derivative is a multiple of 5, cf. A003415.

0, 1, 6, 21, 25, 26, 32, 36, 46, 50, 51, 75, 76, 86, 88, 91, 99, 100, 106, 111, 112, 116, 125, 126, 141, 146, 150, 156, 161, 166, 175, 192, 200, 201, 206, 209, 216, 221, 225, 226, 236, 242, 243, 248, 250, 266, 272, 275, 276, 279, 291, 300, 301, 306, 308, 316, 319, 321, 325, 326, 328, 346, 350, 356, 369, 371, 375, 381

Offset: 1

Author

Antti Karttunen, Sep 30 2019

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A003415, A235992, A327863, A327864, A327935 (a subsequence).

Programs

PARI

A003415(n) = {my(fac); if(n<1, 0, fac=factor(n); sum(i=1, matsize(fac)[1], n*fac[i, 2]/fac[i, 1]))}; \\ From A003415
isA327865(n) = !(A003415(n)%5);
k=1; n=0; while(k<105, if(isA327865(n), print1(n, ", "); k++); n++);