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A350766
Reversed sum of the two previous terms, with a(1) = 1 and a(2) = 11.
0
1, 11, 21, 23, 44, 76, 21, 79, 1, 8, 9, 71, 8, 97, 501, 895, 6931, 6287, 81231, 81578, 908261, 938989, 527481, 746641, 2214721, 2631692, 3146484, 6718775, 9525689, 46444261, 5996955, 61214425, 8311276, 10752596, 27836091, 78688583
OFFSET
1,2
COMMENTS
Given two initial terms, sum the terms and reverse the digits of the sum. Then repeat.
Related to A014258, the Iccanobif numbers, but with initial terms 1 and 11 rather than 0 and 1.
MATHEMATICA
Clear[ BiF ]; BiF[ 0 ]=1; BiF[ 1 ]=11; BiF[ n_Integer ] := BiF[ n ]=Plus@@(IntegerDigits[ BiF[ n-2 ]+BiF[ n-1 ], 10 ]//(#*Array[ 10^#&, Length[ # ], 0 ])&); Array[ BiF, 40, 0 ]
nxt[{a_, b_}]:={b, FromDigits[Reverse[IntegerDigits[a+b]]]}; Transpose[ NestList[ nxt, {0, 1}, 40]][[1]]
PROG
(Python)
terms = [1, 11]
for i in range(100):
terms.append(int(str(terms[-1]+terms[-2])[::-1]))
print(terms) # Gleb Ivanov, Jan 14 2022
CROSSREFS
Cf. A014258 but with initial terms 1 and 11 rather than 0 and 1.
Sequence in context: A178413 A050718 A360372 * A189226 A261409 A195100
KEYWORD
nonn,base,easy
AUTHOR
Tim Ricchuiti, Jan 14 2022
STATUS
approved