A066960 Duplicate of A061827.
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 7, 5, 4, 4, 3, 3, 3, 3, 1, 11, 1, 4, 7, 3, 5, 2, 4, 2, 1, 11, 6, 1, 3
Offset: 1
This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
a(98) = #{98, 10*9+8, 2*9+10*8} = 3; a(99) = #{99, 11*9} = 2; a(100) = #{100, 10*10, 9*10+10*1, 8*10+20*1, 7*10+30*1, 6*10+40*1, 5*10+50*1, 4*10+60*1, 3*10+70*1, 2*10+80*1, 10+90*1, 100*1} = 12; a(101) = #{101, 10*10+1, 9*10+11*1, 8*10+21*1, 7*10+31*1, 6*10+41*1, 5*10+51*1, 4*10+61*1, 3*10+71*1, 2*10+81*1, 10+91*1, 101*1} = 12; a(102) = #{102, 10*10+2, 10*10+2*1, 9*10+6*2, ...} = 298.
import Data.List (isInfixOf) a119999 n = p (filter ((`isInfixOf` show n) . show) [1..n]) n where p _ 0 = 1 p [] _ = 0 p ks'@(k:ks) m | m < k = 0 | otherwise = p ks' (m - k) + p ks m -- Reinhard Zumkeller, Aug 14 2011
is(n, base=10) = #Set(select(sign, digits(n, base)))==1 \\ Rémy Sigrist, Mar 28 2020
a(n,base=10) = { for (w=0, oo, if (n<=(base-1)*2^w, my (d=1+(n-1)\2^w, k=2^w+(n-1)%(2^w)); return (d*fromdigits(binary(k), base)), n -= (base-1)*2^w)) } \\ Rémy Sigrist, Mar 28 2020
A125289_list = [n for n in range(10**4) if len(set(str(n))-{'0'})==1] # Chai Wah Wu, Jan 04 2015
from itertools import count, product, islice def A125289_gen(): # generator of terms yield from (int(d+''.join(m)) for l in count(0) for d in '123456789' for m in product('0'+d,repeat=l)) A125289_list = list(islice(A125289_gen(),20)) # Chai Wah Wu, Mar 14 2025
a125290 n = a125290_list !! (n-1) a125290_list = filter ((> 1) . a043537) a052382_list -- Reinhard Zumkeller, Jun 18 2013
Select[Range[200], FreeQ[#, 0] && Length[Union[#]] > 1 & [IntegerDigits[#]] &] (* Paolo Xausa, May 06 2024 *)
def ok(n): s = set(str(n)); return len(s) >= 2 and "0" not in s print([k for k in range(124) if ok(k)]) # Michael S. Branicky, Dec 13 2021
a(20) = 2, the only partitions permitted are 20 and 2+2+2...ten times. a(21) = 16, 5 more than A061827 as the partition 12 + 2+2+2+2+1 etc. ( 5 in number) are also considered. a(21) = 17. The allowed parts are 1, 2, 12 and 21. The 17 sums are 21, 12+2+2+2+2+1, 12+2+2+2+1+1+1, 12+2+2+1+1+1+1+1, 12+2+1+1+1+1+1+1+1, 12+1+1+1+1+1+1+1+1+1+1 and 11 more involving only 1 and 2.
a(12) = #{9+3,8+4,7+5,6+6,6+3+3,5+4+3,4+4+4,3+3+3+3} = 8; a(13) = #{9+4,9+2+2,8+5,7+6,7+4+2,7+2+2+2,6+5+2,5+4+4,5+4+2+2,5+2+2+2+2} = 10.
a(n)={my(S=Set(digits(n))); polcoef(1/prod(k=1, 9, 1 - if(!setsearch(S,k), x^k) + O(x*x^n)), n)} \\ Andrew Howroyd, Feb 02 2020
a(7) = #{7, 7x1} = 2; a(8) = #{8, 4+4, 2+2+2+2, 8x1} = 4; a(9) = #{9, 3+3+3, 9x1} = 3; a(10) = #{10, 5+5, 2+2+2+2+2, 10x1} = 4; a(11) = #{11, 10+1, 11x1} = 3; a(12) = #{12, 11+1, 10+1+1, 6+6, 4+4+4, 3+3+3+3, 6x2, 10x1} = 8; a(13) = #{13, 12+1, 11+1+1, 10+1+1+1, 13x1} = 5; a(14) = #{14, 13+1, 12+2, 12+1+1, 11+1+1+1, 10+4x1, 7+7, 7x2, 14x1} = 9.
import Data.List (intersect) a193513 n = p "0123456789" n 1 where p "" = 0 p 0 = 1 p cds m k | m < k = 0 | otherwise = p (cds `intersect` show k) (m - k) k + p cds m (k + 1)
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