A247624 Knife numbers (first version): n=concat(a,b) is divisible by a+b; a,b>0.

12, 18, 21, 24, 27, 36, 42, 45, 48, 54, 63, 72, 81, 84, 105, 108, 110, 126, 132, 144, 147, 162, 168, 189, 198, 216, 220, 231, 243, 264, 288, 297, 324, 330, 396, 405, 414, 418, 429, 432, 440, 462, 486, 495, 510, 528, 540, 550, 567, 594, 612, 616, 621, 627, 648, 660, 693, 714, 726, 729, 756, 770, 792, 810, 814, 816, 825, 828, 836

Offset

1,1

Comments

It is understood that b does not have leading zeros.

This is a subsequence of A247625, A247626 and A247627 which allow b to have leading zeros or to be zero.

Links

Table of n, a(n) for n=1..69.

E. Angelini, Knife numbers.

Prog

(PARI) is(n, u=[1, 1])=n&&for(k=1, #Str(n)-1, n%(u*divrem(n, 10^k))==0&&(n%10^k>=10^(k-1))&&return(1))

Crossrefs

Sequence in context: A362052 A247625 A171674 * A031207 A107794 A280014

Adjacent sequences: A247621 A247622 A247623 * A247625 A247626 A247627

Keyword

nonn,base

Author

M. F. Hasler and Eric Angelini, Sep 21 2014

Status

approved