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A327865
Numbers whose arithmetic derivative is a multiple of 5, cf. A003415.
10
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
1,3
LINKS
PROG
(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++);
CROSSREFS
Cf. A003415, A235992, A327863, A327864, A327935 (a subsequence).
Sequence in context: A323916 A364202 A323917 * A369969 A229498 A164698
KEYWORD
nonn
AUTHOR
Antti Karttunen, Sep 30 2019
STATUS
approved